JP5160377B2 - Hot water storage water heater - Google Patents

Description

The present invention is a hot water storage tank in which water is supplied through a water supply path connected to the bottom and hot water is sent out through a hot water supply path connected to the upper part,
A tank detour water supply path that detours the hot water tank and supplies water to the hot water supply path;
A tank delivery switching valve that is switchable between a tank delivery permitting state in which the hot water supply path is opened and hot water delivery from the hot water storage tank is permitted, and a tank delivery stop state in which the hot water supply path is closed and the tank bypass water supply path is opened. ,
The present invention relates to a hot water storage type hot water supply device provided with operation control means for controlling operation.

Such a hot water storage type hot water supply apparatus is installed in, for example, a general household and supplies hot water to a hot water consumption section such as a kitchen or a bath. In the state where the tank delivery switching valve is switched to the tank delivery permissible state, Hot water is supplied to the hot water consumption section using hot water from the hot water tank sent from the upper part of the hot water tank through the channel, and the hot water tank is passed through the tank bypass water supply channel when the tank delivery switching valve is switched to the tank delivery stop state. The hot water supply to the hot water consumption section is performed using the water supplied to the hot water supply path, bypassing.
Incidentally, a heating means for heating the hot water in the hot water tank is provided, and moreover, generally a heating means for heating the hot water flowing through the hot water supply path is also provided so that the temperature of the hot water supplied to the hot water consumption section is a target. When the temperature is lower than the hot water supply temperature, the hot water supplied to the hot water consumption section is supplementarily heated by the heating means provided in the hot water supply passage.

The reason for switching the tank delivery switching valve to the tank delivery stop state will be described. In such a hot water storage type hot water supply device, the quality of the hot water in the hot water storage tank decreases due to, for example, a longer time for hot water to be stored in the hot water storage device. If there is a possibility that the quality of the hot water in the hot water tank may be lowered, the tank delivery switching valve can be switched to the tank delivery stop state to supply the hot water with reduced water quality to the hot water consumption section. I try to prevent it. (For example, refer to Patent Document 1).
By the way, while the tank delivery switching valve is switched to the tank delivery stop state, water quality improvement processing such as heating the hot water of the entire hot water storage tank to the preset temperature for water quality improvement is executed, and the quality of the hot water in the hot water storage tank Will be improved.

JP 2006-29745 A

  By the way, even if the tank delivery switching valve is controlled to be switched to the tank delivery stop state, a tank delivery stop failure that prevents the hot water supply path from being closed due to biting of foreign matter or damage to parts, etc. When such a failure occurs, when the tank delivery switching valve is switched to the tank delivery stop state, hot water whose water quality may be deteriorated is supplied to the hot water consumption section.

  The present invention has been made in view of such circumstances, and an object of the present invention is to provide a hot water storage type hot water supply apparatus that can accurately detect a tank delivery stop failure of a tank delivery switching valve.

The hot water storage type hot water supply apparatus of the present invention is a hot water storage tank in which water is supplied through a water supply path connected to the bottom part and hot water is sent through a hot water supply path connected to the upper part,
A tank detour water supply path that detours the hot water tank and supplies water to the hot water supply path;
A tank delivery switching valve that is switchable between a tank delivery permitting state in which the hot water supply path is opened and hot water delivery from the hot water storage tank is permitted, and a tank delivery stop state in which the hot water supply path is closed and the tank bypass water supply path is opened. ,
An operation control means for controlling the operation, and
The first characteristic configuration is that the operation control means is closed by the operation process for determination for switching the tank delivery switching valve to the tank delivery stop state when the failure judgment timing comes, and the tank delivery switching valve in the hot water supply channel. It is configured to execute a failure determination process for determining whether or not it is a tank delivery stop failure state based on the temperature change of the hot water in the hot water tank side or the hot water in the hot water tank relative to the place where In the point.

  That is, the operation control means, when the failure determination timing comes, the determination operation processing for switching the tank delivery switching valve to the tank delivery stop state, and the portion on the hot water storage tank side from the location closed by the tank delivery switching valve in the hot water supply channel A failure determination process is performed to determine whether or not the tank delivery stop failure state is based on the temperature change of the hot water or the hot water in the hot water storage tank.

  In other words, when the hot water supply path is closed when the tank delivery switching valve is controlled to be switched to the tank delivery stop state, the portion on the hot water consumption section side of the hot water supply passage is closed by the tank delivery switching valve. Even if hot water in other flow paths connected to the part flows, the hot water flows in the hot water tank side part and the hot water tank than the part closed by the tank delivery switching valve in the hot water supply path. If the tank delivery switching valve is controlled to be switched to the tank delivery stop state but the hot water supply path is not closed, the tank delivery switching valve in the hot water supply path When hot water in the hot water consumption section side of the part to be closed or other hot water in the other flow passage connected to that part flows, the hot water is closed by the tank delivery switching valve in the hot water supply path. Where you can be Also, the hot water flows in the hot water tank side and the hot water tank, and with such hot water flow, the hot water tank side portion of the hot water channel is closer to the portion closed by the tank delivery switching valve. Since the temperature of the hot water or hot water in the hot water storage tank changes, the tank delivery switching valve is controlled to be switched to the tank delivery stop state based on such a temperature change of the hot water. Thus, it is possible to determine whether or not the tank delivery stop failure state cannot be closed.

By the way, adding the explanation that the temperature of the hot water in the hot water tank side or the hot water in the hot water tank changes from the location closed by the tank delivery switching valve in the hot water supply channel, the tank delivery switching valve is in the tank delivery stop state In a state where the hot water supply passage is not closed despite being controlled to be switched to the hot water supply passage, the portion closer to the hot water consumption section than the portion closed by the tank delivery switching valve in the hot water supply passage, or that portion When hot water in another flow path connected to the fluid flows, the hot water flows in the hot water tank from the bottom to the top, and is closed by the tank delivery switching valve in the hot water supply path. From the form where the part on the hot water storage tank side flows toward the tank delivery switching valve and passes through the tank delivery switching valve, or the place passing through the tank delivery switching valve and closed by the tank delivery switching valve in the hot water supply channel Also on the hot water tank side Flow into the hot water storage tank, and a flow of hot water in a form flowing from the top to the bottom of the hot water storage tank is generated. As a result, the tank delivery switching valve in the hot water supply channel is generated. The temperature distribution in the hot water flow direction changes in the portion closer to the hot water tank than the location closed at, and the temperature distribution in the vertical direction changes in the hot water tank.
Therefore, it has become possible to provide a hot water storage type hot water supply apparatus that can accurately detect a tank delivery stop failure of the tank delivery switching valve.

In addition to the first feature configuration, the second feature configuration is
Hot water supply state detection means for detecting a hot water supply state in which hot water is supplied to the hot water consumption section through the hot water supply path is provided,
When the operation control means detects that the hot water supply state is detected by the hot water supply state detection means in the failure determination process, the temperature of the hot water in the upper part of the hot water storage tank or in the bottom part of the hot water storage tank decreases. It is in the point which is comprised so that it may discriminate | determine that it is a stop failure state.

That is, the hot water tap at the tip of the hot water supply passage is opened while the hot water supply passage is not closed in spite of being controlled so that the tank delivery switching valve is switched to the tank delivery stop state. When the state is reached, water is supplied from the tank detour water supply channel to the hot water supply channel, and the hot water flowing in the form toward the hot water consumption unit side in the portion of the hot water consumption unit side of the hot water supply channel is connected to the tank detour water supply channel. As the hot water flows, the water pressure of the water supply channel causes the water to be supplied from the water supply channel to the bottom of the hot water tank, and the hot water flows from the bottom to the top in the hot water tank. The temperature distribution in the vertical direction in the hot water tank changes.
In other words, since hot water is stored in the hot water tank in a form that forms a temperature stratification in which the temperature of the hot water becomes higher upward, as described above, when hot water flows in the hot water tank, The temperature of the hot water and the temperature of the hot water at the bottom of the hot water storage tank will decrease.
Therefore, in the failure determination process, when the hot water supply state is detected by the hot water supply state detection means, if the temperature of the hot water at the upper part of the hot water tank or at the bottom of the hot water tank decreases, it is determined that the tank delivery stop failure state has occurred. By configuring, it is possible to accurately determine that the tank delivery stop failure state.
Then, detecting the hot water supply state in which hot water is supplied to the hot water consumption unit through the hot water supply path is necessary for, for example, processing for adjusting the temperature of the hot water supplied to the hot water consumption unit to the target hot water supply temperature. Usually, hot water supply state detecting means for detecting the hot water supply state is provided.
Therefore, the tank delivery stop failure can be accurately detected without adding a new member to determine whether or not the tank delivery stop failure state has occurred.

In addition to the first feature configuration, the third feature configuration is
The tank bypass water supply channel is branched from the water supply channel and connected to the hot water supply channel;
The tank detour water supply path has a tank detour water supply opening / closing valve that opens and closes the tank detour water supply path, and an additional circulation means that causes hot water to flow toward the hot water supply path. Is located in the state,
A portion of the hot water supply channel that is further away from the hot water storage tank than a portion to which the tank bypass water supply channel is connected; a portion of the tank bypass water supply channel that is between the tank bypass water supply channel opening / closing valve and the additional circulation means; An additional circuit portion connected to the
The operation control means is configured to open the tank bypass water supply opening / closing valve and operate the additional circulation means in the determination operation process, and in the failure determination process, the tank in the hot water supply path. It is configured to determine whether or not the tank delivery stop failure state is based on the temperature change of the hot water in the hot water tank side portion or the hot water in the hot water tank relative to the location closed by the delivery switching valve. There is in point.

That is, when the tank detour water supply opening / closing valve is opened and the additional circulation means is operated, the additional circulation path portion, the portion closer to the hot water supply path than the connection point of the additional circulation path portion in the tank detour water supply channel, and the hot water supply Direction through the additional circulation path that passes through the portion on the side farther away from the hot water storage tank than the connection point of the tank bypass water supply path in the channel, and the direction toward the hot water supply channel side from the connection point of the additional circulation path part in the tank bypass water supply channel Although hot water is circulated in the tank, and the hot water is circulated through the additional circulation path as described above, the tank delivery switching valve is controlled to be switched to the tank delivery stop state. When the passage is not closed, a part of the hot water that flows toward the hot water supply passage through the hot water supply passage side of the additional circulation passage portion of the tank bypass water supply passage passes through the tank delivery switching valve. Therefore, it is allowed to flow into the hot water storage tank side portion rather than the location closed by the tank delivery switching valve in the hot water supply channel, so that the hot water storage tank than the location closed by the tank delivery switching valve in the hot water supply channel In a circulation path (hereinafter sometimes referred to as a hot water tank circulation path) via the side portion, the hot water tank and the tank bypass water supply channel, the hot water flows in the direction from the top to the bottom in the hot water tank. Thus, the temperature of the hot water in the hot water tank side or the hot water in the upper part of the hot water tank changes from the location closed by the tank delivery switching valve in the hot water supply channel.
Therefore, in the failure determination process, when hot water is circulated through the additional circulation path, the temperature change of the hot water in the hot water tank side or the hot water in the upper part of the hot water tank relative to the location closed by the tank delivery switching valve in the hot water supply path Based on the above, it is possible to more accurately determine whether or not it is in the tank delivery stop failure state by determining whether or not it is in the tank delivery stop failure state.
Therefore, it has become possible to detect the tank delivery stop failure more accurately.

In addition to the third feature configuration, the fourth feature configuration is
The temperature of the hot water in the hot water tank side or in the upper part of the hot water tank is higher than the temperature of the hot water in the hot water tank than the location where the operation control means is closed by the tank delivery switching valve in the hot water supply path in the failure determination process. An additional circulation path that passes through a circulation path portion, a portion on the hot water supply path side of the connection place of the additional circulation path portion in the tank bypass water supply path, and a downstream portion of the connection area of the tank bypass water supply path in the hot water supply path When the temperature of hot water in the hot water storage tank is lower than the location closed by the tank delivery switching valve in the hot water supply path or when the temperature of hot water in the upper part of the hot water storage tank decreases, It is in the point which is comprised so that it may discriminate | determine that it is a stop failure state.

That is, when the temperature of the hot water in the hot water tank side or the hot water in the upper part of the hot water tank is higher than the temperature of the hot water in the additional circulation path from the location closed by the tank delivery switching valve in the hot water supply channel, the tank delivery switching valve If the hot water supply path is not closed in spite of being controlled to be switched to the tank delivery stop state, when hot water is circulated through the additional circulation path, the hot water tank circulation path When hot water flows in the direction from the top to the bottom, the hot water in the additional circulation path is added to the hot water on the hot water tank side and the hot water in the upper part of the hot water tank rather than the part closed by the tank delivery switching valve in the hot water supply path. As a result of mixing, the temperature of the hot water in the hot water tank side or the hot water in the upper part of the hot water tank is lower than the location closed by the tank delivery switching valve in the hot water supply channel.
Therefore, in the failure determination process, when the temperature of the hot water in the hot water tank side or the hot water in the upper part of the hot water tank is higher than the temperature of the hot water in the additional circulation path from the location closed by the tank delivery switching valve in the hot water path. When the hot water is circulated through the additional circulation path, if the temperature of the hot water in the hot water tank side or the hot water in the upper part of the hot water tank is lower than the location closed by the tank delivery switching valve in the hot water path, the tank delivery stoppage failure By configuring so as to determine that it is in the state, it is possible to accurately determine whether or not it is a tank delivery stop failure state.

By the way, hot water is circulated through the additional circulation path, and the tank delivery is stopped based on the temperature change of the hot water in the hot water tank side or the hot water in the upper part of the hot water tank than the place closed by the tank delivery switching valve in the hot water supply path. In determining whether or not there is a failure state, hot water in the hot water storage tank or the additional circulation path is forcibly heated, and the hot water in the hot water tank side from the location closed by the tank delivery switching valve in the hot water supply path or Although it is conceivable to make the temperature of the hot water in the hot water tank different from the temperature of the hot water in the additional circulation path, the hot water in the hot water tank side or the part that is closed by the tank delivery switching valve in the hot water path When the temperature of the hot water in the upper part of the hot water storage tank is higher than the temperature of the hot water in the additional circulation path, it is determined whether or not it is in the tank delivery stop failure state as described above. It is possible to suppress the formic consumption.
In other words, the hot water stored in the hot water tank is not easily lowered due to the heat retaining function of the hot water tank, whereas the hot water in the additional circulation circuit is easy to cool and low in temperature. The state where the temperature of hot water in the hot water tank side or the temperature of hot water in the upper part of the hot water tank is higher than the temperature of hot water in the additional circulation path from the location closed by the tank delivery switching valve in the tank frequently appears with use. And, in such a state, since it is possible to determine whether or not it is a tank delivery stop failure state simply by operating the additional circulation means, it is unnecessary to heat hot water in the failure determination process, Energy consumption can be suppressed.
Accordingly, it has become possible to accurately detect a tank delivery stop failure while suppressing energy consumption.

In addition to the third feature configuration, the fifth feature configuration includes:
In the hot water supply path, an additional heating means for heating the hot water supplied to the hot water supply path portion located between the connection location to which the tank bypass water supply channel is connected and the connection location to which the additional circulation path portion is connected. Is provided,
The operation control means is configured to heat the additional heating means in addition to operating the additional circulation means in the determination operation processing, and in the failure determination processing, the operation control means is configured to operate the additional heating means in the hot water supply path. It is configured to discriminate that the tank delivery stop failure state occurs when the temperature of the hot water in the hot water tank side or the hot water in the upper part of the hot water tank rises higher than the location closed by the tank delivery switching valve. It is in.

That is, in the discrimination operation process, when hot water is circulated through the additional circulation path, the temperature of the hot water in the additional circulation path is closed by the tank delivery switching valve in the hot water supply path by heating the additional heating means. The temperature of the hot water at the hot water tank side or the temperature of the hot water at the upper part of the hot water tank can be made higher, and when the hot water of the additional circuit is mixed, It is possible to make the width such that the temperature rise of the hot water in the hot water tank side or the hot water in the upper part of the hot water tank appears more remarkably than the location closed by the delivery switching valve.
When the discrimination operation process is executed in this manner, the hot water supply passage is not closed in spite of being controlled so that the tank delivery switching valve is switched to the tank delivery stop state. As the temperature rise of the hot water in the hot water tank side or the hot water in the upper part of the hot water tank will appear more markedly than the location closed by the tank delivery switching valve in the road, whether or not it is a tank delivery stop failure state It is possible to discriminate more accurately.
Therefore, it has become possible to detect the tank delivery stop failure more accurately.

In addition to the fifth feature configuration, the sixth feature configuration is
In the operation process for determination, the operation control means is configured so that the hot water supplied in the hot water tank is closer to the hot water tank or the hot water in the hot water tank than the place where the hot water supply channel is closed by the tank delivery switching valve. The heating operation of the additional heating means is controlled to heat to a temperature higher than the temperature.

That is, the temperature of the hot water in the hot water tank side or the hot water in the hot water tank is detected from the location closed by the tank delivery switching valve in the hot water supply channel, and in the determination operation process, by the additional heating means, The hot water in the additional circuit is heated to a temperature higher than the detected temperature.
That is, when the tank delivery switching valve is controlled so as to be switched to the tank delivery stop state, but the hot water supply passage is not closed, it is more than the portion closed by the tank delivery switching valve in the hot water supply passage. In order to raise the temperature of the hot water in the hot water tank side or the hot water in the upper part of the hot water tank significantly by mixing the hot water in the additional circuit, when heating the hot water in the additional circuit by the additional heating means, Because the temperature of the hot water in the hot water tank side or the hot water in the upper part of the hot water tank is detected from the location closed by the tank delivery switching valve in the hot water supply channel, and the temperature is higher than the detected temperature. When the detected temperature is low, the set temperature is heated higher than the low temperature, and when the detected temperature is high, the set temperature is heated higher than the set temperature. Therefore, energy consumption can be reduced compared to the case where the temperature is always set higher than the temperature of hot water that is expected to be stored in the hot water tank. Is possible.
Therefore, it has become possible to more accurately detect a tank delivery stop failure while suppressing energy consumption.

In addition to any one of the first to sixth feature configurations described above, the seventh feature configuration is
In addition to the tank delivery switching valve, a tank delivery suppression valve that suppresses the delivery of hot water from the hot water storage tank is provided,
When it is determined that the operation control means is in the tank delivery stop failure state, it is configured to execute a failure countermeasure process for controlling the operation of the tank delivery suppression valve to suppress delivery of hot water from the hot water storage tank. There is in point.

That is, when it is determined that the tank delivery stop failure state has occurred, a failure countermeasure process for controlling the operation of the tank delivery suppression valve is performed to suppress the delivery of hot water from the hot water storage tank, and the hot water storage tank As a result, the supply of hot water that may have deteriorated in water quality can be appropriately suppressed from being supplied to the hot water consumption section.
Therefore, even if a tank delivery stop failure occurs, it is possible to appropriately suppress the supply of hot water that may have deteriorated water quality to the hot water consumption section.

In addition to the seventh feature configuration, the eighth feature configuration is
A downstream water supply channel for supplying water to a location downstream from the location where the tank bypass water supply channel in the hot water supply channel is connected;
A mixing ratio control valve capable of adjusting a mixing ratio of water supplied through the downstream water supply passage and hot water from the hot water tank supplied through the hot water supply passage;
The tank delivery suppression valve is composed of the mixing ratio adjustment valve,
The operation control means executes a process for controlling the operation of the mixing ratio adjusting valve so that the ratio of the hot water from the hot water tank to the amount of mixed hot water is 0 or substantially 0 as the failure countermeasure process. It is in the point which is comprised.

That is, the tank feed suppression valve is composed of a mixing ratio adjusting valve, and as a countermeasure against failure, the mixing ratio adjusting valve is operated so that the ratio of hot water from the hot water tank to the amount of mixed hot water is 0 or substantially zero. Since the process to be controlled is executed, the mixing ratio adjustment valve stops the delivery of hot water from the hot water tank or becomes a minute amount.
That is, in such a hot water storage type hot water supply apparatus, the downstream water supply passage and the mixing ratio adjustment valve are usually provided, and when the hot water in the hot water tank is higher than the hot water supply target temperature, The mixing ratio adjustment valve adjusts the mixing ratio of the water supplied through the downstream water supply channel and the hot water from the hot water tank supplied through the hot water supply channel so that the hot water is supplied to the hot water consumption unit. . The mixing ratio adjustment valve is configured to integrally include a valve portion for adjusting the amount of water supplied through the downstream water supply passage and a valve portion for adjusting the amount of hot water supplied through the hot water supply passage. In some cases, each of the pair of valve portions is configured as a separate valve.
When it is determined that the tank delivery stop failure state has occurred, the operation of the mixing ratio adjustment valve is controlled so that the ratio of hot water from the hot water tank to the amount of mixed hot water is 0 or substantially zero. Thus, it is possible to accurately prevent hot water that may have been deteriorated in water quality from being supplied to the hot water consumption section.
Therefore, even if a tank delivery stop failure occurs, it is possible to accurately prevent hot water that may have been deteriorated in water quality from being supplied to the hot water consumption section using the mixing ratio control valve.

In addition to the seventh feature configuration, the ninth feature configuration is
A downstream water supply channel is provided for supplying water to a location downstream from the location where the tank bypass water supply channel in the hot water supply channel is connected;
The tank delivery suppression valve is configured to be able to intermittently supply water to the hot water supply passage by the downstream water supply passage,
The operation control means controls the operation of the tank delivery suppression valve to suppress the delivery of hot water from the hot water storage tank and supply water to the hot water supply path in the downstream water supply path as the failure countermeasure process. In that it is configured to run.

That is, as the failure countermeasure process, a process for controlling the operation of the tank delivery control valve to suppress the delivery of hot water from the hot water storage tank and to supply the hot water supply path in the downstream water supply path is executed. The valve suppresses the delivery of hot water from the hot water storage tank, and water is supplied to the hot water supply channel in the downstream water supply channel, so the temperature of the hot water supplied to the hot water consumption unit is higher than the target hot water supply temperature. In addition, the quality of the hot water supplied to the hot water consumption section is improved by the chlorine contained in the water supplied to the hot water supply channel in the downstream water supply channel.
When the temperature of the hot water supplied to the hot water consumption section becomes lower than the hot water supply target temperature and hot water at the hot water supply target temperature cannot be obtained, the user is made aware that a failure has occurred in the hot water supply device. In addition, even if the user uses the hot water supply device, hot water whose water quality has been improved by chlorine is supplied to the hot water consumption section.
Incidentally, in the case where the structure of the tank delivery control valve cannot close the hot water supply passage, the hot water whose water quality has been improved by chlorine can be obtained by configuring so as to execute the failure countermeasure processing according to the ninth characteristic configuration. Since it will be supplied to a consumption part, it is preferable when improving the safety | security in a hygiene aspect.
Therefore, even if a tank delivery stop failure occurs, the safety in terms of hygiene can be further improved.

In addition to the ninth feature configuration, the tenth feature configuration includes:
There is provided a mixing ratio control valve capable of adjusting the mixing ratio of the water supplied through the downstream water supply channel and the hot water from the hot water storage tank supplied through the hot water supply channel, and the mixing ratio control valve supplies the tank. A suppression valve is configured,
The operation control means, as the failure countermeasure process, minimizes or substantially minimizes the ratio of hot water from the hot water tank and maximizes or substantially maximizes the ratio of water supplied through the downstream water supply channel. It is the point which is comprised so that the process which controls the action | operation of a control valve may be performed.

That is, the tank feed suppression valve is configured by a mixing ratio adjustment valve, and as a countermeasure against failure, the ratio of hot water from the hot water tank is minimized or substantially minimized, and the ratio of water supplied through the downstream water supply channel is maximized or substantially reduced. Since the processing for controlling the operation of the mixing ratio control valve is performed to maximize the ratio of the water from the downstream water supply path in the hot water supplied to the hot water consumption section, the hot water supplied to the hot water consumption section The temperature of the hot water is considerably lower than the target hot water supply temperature, and the quality of the hot water supplied to the hot water consumption section is further improved by the chlorine contained in the water from the downstream water supply channel.
Then, when the temperature of the hot water supplied to the hot water consumption section is considerably lower than the target hot water supply temperature and hot water at the target hot water supply temperature cannot be obtained, the user is more clearly aware that the hot water supply device has failed. It is possible to motivate to stop using the hot water supply device, and even if the user uses the hot water supply device, hot water with further improved water quality is supplied to the hot water consumption section. Become.

That is, as described above in the description of the eighth characteristic configuration, in such a hot water storage type hot water supply apparatus, normally, when the hot water in the hot water tank is higher than the hot water supply target temperature, the hot water supply section is supplied. In order to adjust the temperature of the hot water to be supplied to the hot water supply target temperature, a mixing ratio adjustment valve is provided, and when it is determined that the tank delivery stop failure state has occurred, the mixing ratio adjustment valve is used. Therefore, it is possible to execute failure countermeasure processing that is preferable for improving safety in terms of hygiene.
Therefore, even if the tank delivery stop failure occurs, the hygiene safety can be further improved by using the mixing ratio adjusting valve.

In addition to the ninth feature configuration, the eleventh feature configuration is
A mixing ratio adjusting valve capable of adjusting a mixing ratio of water supplied through the downstream water supply passage and hot water from the hot water tank supplied through the hot water supply passage;
High temperature equipped with a high temperature hot water avoidance valve that supplies water to a location downstream of the location where the downstream water supply channel is connected in the hot water supply channel, and opens in a state where power for opening / closing operation is not supplied There is a hot water avoidance water supply channel,
The tank delivery suppression valve is composed of the mixing ratio adjustment valve and the high temperature hot water avoidance valve,
The operation control means controls the operation of the mixing ratio adjustment valve to minimize or substantially minimize the ratio of hot water from the hot water tank and opens the high temperature hot water avoidance valve as the failure countermeasure process. Therefore, it is configured to execute a process for controlling the operation of the high temperature hot water avoidance valve.

In other words, the tank delivery control valve is composed of a mixing ratio adjustment valve and a high temperature hot water avoidance valve, and controls the operation of the mixing ratio adjustment valve to minimize or substantially minimize the ratio of hot water from the hot water tank as a countermeasure against failure. And the process which controls the action | operation of the high temperature hot water avoidance valve in order to open a high temperature hot water avoidance valve is performed, and the ratio of the water from the high temperature hot water avoidance water supply path in the hot water supplied to the hot water consumption part becomes large Therefore, the temperature of the hot water supplied to the hot water consumption section is considerably lower than the target hot water supply temperature, and the quality of the hot water supplied to the hot water consumption section is further increased by the chlorine contained in the water from the hot hot water supply avoiding water supply channel. Will be improved.
Then, when the temperature of the hot water supplied to the hot water consumption section is considerably lower than the target hot water supply temperature and hot water at the target hot water supply temperature cannot be obtained, the user is more clearly aware that the hot water supply device has failed. It is possible to motivate to stop using the hot water supply device, and even if the user uses the hot water supply device, hot water with further improved water quality is supplied to the hot water consumption section. Become.

That is, in such a hot water storage type hot water supply device, when the hot water in the hot water tank is higher than the target hot water supply temperature, the mixing ratio adjustment is performed to adjust the temperature of the hot water supplied to the hot water consumption section to the target hot water supply temperature. In addition to the provision of a valve, in order to prevent hot water hotter than the hot water supply target temperature from being supplied to the hot water consumption section, the operation of the mixing ratio adjustment valve is not controlled in the event of a power failure. Normally, a high temperature hot water avoidance valve is provided, and when a power failure occurs, the high temperature hot water avoidance valve opens, and water from the high temperature hot water supply avoidance water supply channel is mixed with hot water in the hot water supply channel, so Supply of hot water having a temperature higher than the hot water supply target temperature is prevented.
And, when it is determined that it is a tank delivery stop failure state, it is configured to control the mixing ratio adjustment valve and the high-temperature hot water avoidance valve as described above, thereby improving hygiene safety. A preferable failure countermeasure process can be executed.
Therefore, even if the tank delivery stop failure occurs, the hygiene safety can be further improved by using the mixing ratio adjusting valve and the high temperature hot water avoidance valve.

In addition to any one of the first to sixth characteristic configurations, the twelfth characteristic configuration is
A downstream water supply channel for supplying water to a location downstream from the location where the tank bypass water supply channel in the hot water supply channel is connected;
A water supply amount adjustment valve for adjusting the amount of water supplied through the downstream water supply channel,
When the operation control means determines that the tank delivery stop failure state is present, the tank delivery switching valve is maintained in the tank delivery stop state, and the opening of the water supply amount adjustment valve is maximized or substantially maximized. A failure countermeasure process for controlling the operation of the water supply amount adjustment valve to be adjusted is executed.

That is, when it is determined that the tank delivery stop failure state has occurred, the water supply amount adjustment valve is maintained so that the tank delivery switching valve is maintained in the tank delivery stop state and the opening of the water supply amount adjustment valve is adjusted to the maximum or substantially maximum. Therefore, a large amount of water is supplied to a location downstream of the location where the tank bypass water supply channel is connected in the hot water supply channel through the lower water supply channel.
In this way, through the tank delivery switching valve in the tank delivery stop state, a large amount of water is supplied to the downstream side of the place where the tank bypass water supply path in the hot water supply path is connected through the lower water supply path, Even if hot water from the hot water storage tank leaks downstream from the place where the tank bypass water supply path is connected in the hot water supply path, the hot water supply path is caused by dilution with a large amount of water supplied through the lower water supply path. The quality of the hot water supplied through the water can be improved, and it is possible to appropriately suppress the supply of hot water having a possibility that the water quality has deteriorated to the hot water consumption section.
Therefore, even if a tank delivery stop failure occurs, it is possible to appropriately suppress the supply of hot water that may have deteriorated water quality to the hot water consumption section.

The thirteenth feature configuration, in addition to any one of the first to twelfth feature configurations,
An internal circulation path formed by using a part of the downstream portion of the hot water supply path where the tank bypass water supply path is connected;
An internal circulation means for circulating hot water through the internal circulation path is provided,
An internal circulation path downstream on-off valve that opens and closes the hot water supply path is provided in a portion on the downstream side of the part forming the internal circulation path in the hot water supply path,
The operation control means is configured to execute an internal circulation operation of operating the internal circulation circulation means to circulate hot water through the internal circulation path based on an internal circulation operation start command, and When it is determined that the tank delivery stop failure state has not occurred, the internal circulation operation is performed with the internal circulation path downstream side open / close valve opened, and when it is determined that the tank delivery stop failure state has occurred, The internal circulation operation is performed in a state where the downstream opening / closing valve on the downstream side of the circulation path is closed.

In other words, if it is determined that the internal circulation operation start command is not in the tank delivery stop failure state, the internal circulation operation is executed with the internal circulation path downstream open / close valve opened, and the tank delivery stop failure occurs. When it is determined that the state is the state, the internal circulation operation is executed with the internal circulation path downstream side on-off valve closed.
Then, when the internal circulation operation is being performed with the internal circulation path downstream side open / close valve opened, if the hot water tap or the like at the tip of the hot water supply path is opened, the hot water in the hot water tank is sent out. When the internal circulation operation is being performed with the on-off valve on the downstream side of the internal circulation path closed, the hot water supply tap at the tip of the hot water supply path is opened. However, the hot water in the hot water tank is not sent to the hot water supply path.

That is, in such a hot water storage type hot water supply apparatus, an internal circulation path and an internal circulation circulation means are provided, and when an internal circulation operation start command is instructed, the internal circulation circulation means is operated to cause internal circulation. There is a case where it is configured to be able to execute an internal circulation operation in which hot water is circulated through a path.
For example, when a heat radiating section such as a floor heating device or a bathroom heating device is provided, in addition to the internal circulation path and the circulation means for internal circulation, heating means for internal operation for heating hot water circulating through the internal circulation path, and heat radiation And a heat exchanger for heating the heat medium circulated in the section by hot water circulating in the internal circulation path, and in the internal circulation operation, the hot water heated by the heating means for internal operation is circulated through the internal circulation path. Thus, the heat medium circulated in the heat radiating section is heated in the heat exchanger.

And when the start command of the internal circulation operation is commanded when the tank delivery stop failure state is not in effect, not only the internal circulation operation is executed, but also the internal circulation operation start command when it is in the tank delivery stop failure state. The internal circulation operation is executed in a state where hot water in the hot water tank is prevented from being supplied to the hot water consumption unit.
Accordingly, it has become possible to avoid the deterioration of usability such that the internal circulation operation cannot be performed while the safety in terms of hygiene is ensured.

The fourteenth feature configuration, in addition to any one of the first to thirteenth feature configurations,
The failure determination timing is set to a water quality improvement timing for improving the quality of hot water in the hot water tank,
When the operation control means performs the determination operation process and the failure determination process at the timing of improving the water quality, and determines that the tank delivery stop failure state is not present, the hot water storage for heating the hot water in the hot water storage tank When the tank heating means performs a water quality improvement operation for heating the hot water in the entire hot water storage tank to a temperature equal to or higher than the set temperature for water quality improvement, and if it is determined that the tank delivery stop failure state, the water quality improvement operation is executed. The point is that it is configured not to.

That is, since the failure determination timing is set to the water quality improvement timing for improving the quality of the hot water in the hot water tank, the operation control means executes the determination operation process and the failure determination process at the water quality improvement timing, If it is determined in the failure determination process that the tank delivery stop failure state is not present, the hot water storage tank heating means performs a water quality improvement operation in which the hot water in the entire hot water storage tank is heated to a temperature higher than the set temperature for water quality improvement, and is in a tank delivery stop failure state. If it is determined, the water quality improvement operation is not executed.
In other words, when the water quality improvement timing is reached, before performing the water quality improvement operation, first, the determination operation process and the failure determination process are executed, and only when it is determined that the tank delivery stop failure state is not found in the failure determination process. Since the improvement operation is executed, it is possible to avoid the inconvenience of wasting the energy by unnecessaryly executing the water quality improvement operation even if the tank delivery stop valve is repaired or replaced, even if the tank delivery stop valve needs to be repaired or replaced. can do.
Incidentally, when the tank delivery switching valve is repaired or exchanged by an operator or the like, since the hot water of the entire hot water storage is replaced with water from the water supply channel, the water quality improvement operation is unnecessary.
Therefore, the water quality improvement operation is not executed when there is a tank delivery stop failure, and while avoiding energy waste, the water quality improvement operation is executed when the water quality improvement timing is reached. Hot water can be supplied with the water quality maintained appropriately.

In addition to any one of the first to fourth feature configurations and the seventh to thirteenth feature configurations, the fifteenth feature configuration is
The failure determination timing is set to a water quality improvement timing for improving the quality of hot water in the hot water tank,
When the operation control means reaches the water quality improvement timing, the hot water storage tank heating means for heating the hot water in the hot water tank performs a water quality improvement operation for heating the hot water in the entire hot water tank to a temperature higher than the set temperature for water quality improvement. , In that the determination operation process and the failure determination process are executed.

That is, since the failure determination timing is set to the water quality improvement timing for improving the quality of the hot water in the hot water tank, the operation control means uses the hot water tank heating means to remove the hot water from the entire hot water tank when the water quality improvement timing is reached. After executing the water quality improvement operation for heating to the set temperature for improvement or higher, the determination operation process and the failure determination process are executed.
That is, when executing the discrimination operation process and the failure discrimination process, the temperature of the hot water in the entire hot water storage tank is substantially equal to or higher than the set temperature for improving the water quality, so that the tank delivery switching valve is switched to the tank delivery stop state. If the hot water supply channel is not closed in spite of being controlled, the temperature of the hot water at the bottom of the hot water storage tank due to the inflow of water from the water supply channel, or the hot water storage tank due to the inflow of hot water from the hot water supply channel Since the temperature drop of the upper hot water becomes clear, it is possible to more accurately determine the tank delivery stop failure state in the failure determination process.
In particular, in addition to the second feature configuration described above, when the fourteenth feature configuration is implemented, the temperature difference between the temperature of the hot water in the hot water storage tank and the temperature of the water from the water supply channel is large, and the water from the water supply channel is This is preferable because the temperature drop of hot water at the bottom of the hot water storage tank due to the inflow of water becomes remarkable.
Therefore, it has become possible to detect the tank delivery stop failure more accurately.

Hereinafter, an embodiment in the case of applying a hot water storage type hot water supply apparatus according to the present invention to a cogeneration system will be described based on the drawings.
[First Embodiment]
First, the first embodiment will be described.
As shown in FIG. 1, the cogeneration system includes a fuel cell 1 as a combined heat and power generation device that generates electric power and heat, and stores hot water in a hot water tank 2 with the heat generated by the fuel cell 1 and stores the hot water. A hot water supply unit 3 for supplying hot water to a hot water consumption unit such as a kitchen or a bath using hot water stored in the tank 2, and an operation control unit 4 as operation control means for controlling the operation of the fuel cell 1 and the hot water supply unit 3. Etc.

Since the fuel cell 1 is well-known, a detailed description and illustration thereof will be omitted. Briefly, the fuel cell 1 is a cell stack that is supplied with a fuel gas containing hydrogen and an oxygen-containing gas, A fuel gas generation unit that generates fuel gas to be supplied to the cell stack, a blower that supplies air as an oxygen-containing gas to the cell stack, and the like are provided.
The fuel gas generation unit includes a desulfurizer for desulfurizing a hydrocarbon-based raw fuel gas such as a supplied city gas (for example, a natural gas-based city gas), a desulfurized raw fuel gas supplied from the desulfurizer, A reformer that generates a reformed gas mainly composed of hydrogen by reforming reaction with steam supplied separately, and carbon monoxide in the reformed gas supplied from the reformer with carbon dioxide. A carbon monoxide remover that selectively oxidizes carbon monoxide in the reformed gas supplied from the transformer with selective oxidation air supplied separately. The reformed gas reduced by the shift treatment and the selective oxidation treatment is supplied to the cell stack as the fuel gas.
And it is comprised so that the electric power generated of the said fuel cell 1 may be adjusted by adjusting the supply amount of the raw fuel gas to the said fuel gas production | generation part.

A grid interconnection inverter 5 is provided on the power output side of the fuel cell 1, and the inverter 5 has the same voltage and the same frequency as the received power that receives the generated power of the fuel cell 1 from the commercial power source 6. Is configured to do.
The commercial power source 6 is, for example, a single-phase three-wire system 100/200 V, and is electrically connected to a power load 8 such as a television, a refrigerator, or a washing machine via a received power supply line 7.
The inverter 5 is electrically connected to the received power supply line 7 via the generated power supply line 9, and the generated power from the fuel cell 1 is supplied to the power load 8 via the inverter 5 and the generated power supply line 9. It is configured to be.

The received power supply line 7 is provided with load power measuring means 10 for measuring the load power of the power load 8. Does this load power measuring means 10 generate a reverse power flow in the current flowing through the received power supply line 7? It is also configured to detect whether or not.
The electric power supplied from the fuel cell 1 to the received power supply line 7 is controlled by the inverter 5 so that a reverse power flow does not occur, and the surplus power of the power generation output is recovered by replacing the surplus power with heat. 11 is configured to be supplied.

The electric heater 11 is composed of a plurality of electric heaters, and is provided so as to heat the cooling water of the fuel cell 1 flowing through the cooling water circulation path 13 by the operation of the cooling water circulation pump 12. ON / OFF is individually switched by the connected operation switch 14.
The operation switch 14 is configured to adjust the power consumption of the electric heater 11 according to the magnitude of the surplus power so that the power consumption of the electric heater 11 increases as the magnitude of the surplus power increases. Yes.
As for the configuration for adjusting the power consumption of the electric heater 11, in addition to the configuration for switching ON / OFF of the plurality of electric heaters 11 as described above, the configuration for adjusting the output of the electric heater 11 by, for example, phase control or the like. You may adopt.

Hereinafter, the hot water supply unit 3 will be described.
The hot water tank 2 is configured such that water is supplied through a water supply passage 15 connected to the bottom and hot water is sent out through a hot water supply passage 16 connected to the top.
And in addition to the said hot water storage tank 2, the hot water supply unit 3 is the hot water storage circulation path 17 connected to the bottom part and upper part of the hot water storage tank 2, and the hot water storage circuit in the form which returns the hot water taken out from the tank bottom part to the tank upper part. A hot water circulating pump 18 that circulates hot water in the hot water tank 2 through 17, a hot water heat exchanger 19 that heats hot water in the hot water tank 2 that flows through the hot water circulating circuit 17, and a hot water supply path 16 that bypasses the hot water tank 2. The tank detour water supply path 20 for supplying water to the tank, the tank supply permission state for allowing the hot water supply from the hot water storage tank 2 to be opened by opening the hot water supply path 16, and the tank delivery for closing the hot water supply path 16 and opening the tank detour water supply path 17 A tank delivery switching valve V1 that can be switched to a stopped state is provided.

In the first embodiment, the tank bypass water supply channel 20 is branched from the water supply channel 15 and connected to the hot water supply channel 16.
The tank bypass water supply path 20 includes a tank bypass water supply opening / closing valve 21 that opens and closes the tank bypass water supply path 20 and a circulation pump 22 for heat radiation operation as additional circulation means for flowing hot water toward the hot water supply path. Is provided in a state where the tank bypass water supply opening / closing valve 21 is located on the water supply path side.
Further, in the first embodiment, the tank delivery switching valve V1 is connected to the hot water supply upstream port to which the hot water storage tank side portion of the hot water supply passage 16 is connected, and to the hot water consumption section side portion of the hot water supply passage 16. It consists of a three-way valve 23 for tank delivery switching provided with three ports: a hot water supply path downstream port and a water supply path side port to which the tank bypass water supply path 20 is connected.
That is, 2 in a state where each of the hot water supply upstream port and the hot water supply downstream port is opened and the water supply side port is closed, and all three ports of the hot water supply upstream port, the hot water supply downstream port and the water supply side port are opened. The state corresponds to the tank delivery allowance state. In the following description, the former state is referred to as the first tank delivery allowance state, and the latter state is referred to as the second tank delivery allowance state.
Moreover, the state where the hot water supply path upstream port is closed and the hot water supply downstream port and the water supply port are opened respectively corresponds to the tank delivery stop state.

Further, the hot water supply unit 3 includes a portion of the hot water supply passage 16 on the downstream side of the place where the tank bypass water supply passage 20 is connected, a tank bypass water supply opening / closing valve 21 in the tank bypass water supply passage 20 and a circulation pump 22 for heat radiation operation. A heating circulation path portion 24 and a memorial circulation path portion 25 connected to a portion between the two are provided.
Specifically, in a state in which the connection location of the heating circulation path portion 24 to the hot water supply passage 16 is closer to the hot water tank 2 than the connection location of the recirculation circulation path portion 25 to the hot water supply passage 16, 24 and the circulation circuit portion 25 for remedy are connected to the hot water supply passage 16, and the connection place of the circulation circuit portion 24 for heating to the tank detour supply water channel 20 is connected to the tank detour supply water channel 20 of the remedy circulation circuit portion 25. The heating circulation path portion 24 and the remedy circulation path portion 25 are connected to the tank bypass water supply path 20 in a state closer to the hot water supply path 16 than the connection location.
In addition, the heating circuit portion 24 includes a heating circuit portion 24, a portion closer to the hot water supply path than the connection location of the heating circuit portion 24 in the tank bypass water supply channel 20, and the tank bypass water supply channel 20 in the hot water supply channel 16. There is provided a heating on-off valve 26 that intermittently circulates hot water through the heating circulation path R1 passing through a portion downstream of the connection point.
Further, the memorial circuit portion 25 includes a memorial circuit portion 25, a portion closer to the hot water supply path than the connecting portion of the memorial circuit portion 25 in the tank detour water supply channel 20, and a tank detour in the hot water channel 16. A remedy on-off valve 27 is provided to intermittently circulate hot water through the circulatory circulation path R2 that passes through a portion downstream of the connection point of the water supply passage 20.

  Further, a heating circulation pump 30 that circulates the heating medium through the heating medium circulation path 29 to the heating terminal 28 such as a floor heating panel, and heat circulated through the heating medium circulation path 29 by hot water circulated through the heating circulation path R1. A heat exchanger 31 for heating that heats the medium, a circulation pump 34 for circulating hot water in the bathtub 32 through the bathtub hot water circulation path 33, and hot water circulated through the circulation circuit R2 through the bathtub hot water circulation path 33. A remedy heat exchanger 35 for heating the hot and cold water in the tub 32 to be circulated is provided.

An auxiliary heater 36 for heating the hot water flowing through the hot water supply passage 16 is provided in a portion of the hot water supply passage 16 between the connection portion of the tank bypass water supply passage 20 and the connection portion of the heating circulation passage portion 24. ing.
The auxiliary heater 36 includes an auxiliary heating heat exchanger 36a provided in the hot water supply path 16, a burner 36b for heating the auxiliary heating heat exchanger 36a, a fan 36c for supplying combustion air to the burner 36b, An inflow temperature sensor (not shown) for detecting the inflow temperature of hot water flowing into the auxiliary heating heat exchanger 36a, an outflow temperature sensor (not shown) for detecting the temperature of hot water flowing out of the auxiliary heating heat exchanger 36a, and an auxiliary A flow rate sensor (not shown) for detecting the flow rate of hot water flowing into the heat exchanger 36a for heating is provided, and the operation of the auxiliary heater 36 is controlled by the operation control unit 4.

Further, the hot water supply unit 3 has a location downstream of the hot water supply passage 16 where the recirculation circulation passage portion 25 is connected (downstream of the location where the tank bypass water supply passage 20 is connected). A mixing water supply channel 37 serving as a downstream water supply channel that supplies water to the water supply path 37), water supplied through the mixing water supply channel 37, and hot water from the hot water tank 2 supplied through the hot water supply channel 16. A state where water is supplied to a location downstream of the location where the mixing rate adjustment valve V2 and the mixing water supply channel 37 in the hot water supply channel 16 are connected, and power for opening and closing operation is not supplied. And a high-temperature hot-water supply avoiding water supply passage 39 equipped with a high-temperature hot-water supply avoiding valve 38 that is in the open state.
The mixing water supply channel 37 and the high temperature hot water supply avoiding water supply channel 39 are both branched from the water supply channel 15 and connected to the hot water supply channel 16.

  In the first embodiment, the mixing ratio adjusting valve V2 is provided between a location where the recirculation circulation passage portion 25 in the hot water supply passage 16 is connected and a location where the mixing water supply passage 37 is connected. The hot water supply side control valve 40 which can freely adjust the flow of hot water in the hot water supply passage 16 and the flow rate of the hot water supply passage 16, and the water supply flow in the mixing water supply passage 37 provided in the mixing water supply passage 37. It is composed of a mixing water supply side control valve 41 that can freely adjust intermittent and flow rate.

A tank delivery amount sensor 42 that detects the amount of hot water delivered from the hot water storage tank 2 is provided at a location upstream of the connection location of the tank bypass water supply channel 20 in the hot water supply channel 16.
Hot water from the hot water supply passage 16 and the mixing water supply passage at the hot water supply passage side control valve 40 and the mixing water supply passage side adjustment valve 41 at a location downstream of the connection location of the mixing water supply passage 37 in the hot water supply passage 16. A hot water supply temperature sensor 43 for detecting the temperature of the hot water after the mixing ratio with water from 37 is adjusted, and a hot water supply amount sensor 44 for detecting the amount of the hot water are provided.
A heating temperature sensor 45 for detecting the temperature of the hot water heated by the hot water storage heat exchanger 19 is provided at a location downstream of the hot water storage heat exchanger 19 in the hot water storage circuit 17. A tank top temperature sensor 46 for detecting the temperature of the hot water at the top of the hot water tank 2 is provided at the top of the hot water tank 2, and a tank bottom temperature for detecting the temperature of the hot water at the bottom of the water tank 2 is provided at the bottom of the hot water tank 2. A sensor 47 is provided.

Next, the control operation of the operation control unit 4 will be described.
The operation control unit 4 is configured to be able to communicate with a remote operation type operation unit 48, and although not shown in the figure, an operation switch for instructing start and stop of the operation of the fuel cell 1, A hot water supply temperature setting unit for setting a target hot water supply temperature, a heating switch for instructing start and stop of a heating operation for operating the heating terminal 28, and a memorial switch for instructing start and stop of a memorial operation for chasing the bathtub 32 Etc. are provided.

When the start of operation of the fuel cell 1 is instructed by the operation switch of the operation unit 48, the operation control unit 4 causes the fuel cell 1 to make the generated power follow the current load power currently requested. Operate continuously in the main operation.
In the main operation, the current load power is obtained for each relatively short predetermined output adjustment period such as one minute, and the main output that continuously follows the current load power within the generated power adjustment range of the fuel cell 1 is obtained. The operation is performed in such a manner that the power generation output of the fuel cell 1 is adjusted to the determined main power output.
The current load power is measured based on the measured value of the load power measuring means 10 and the output value of the inverter 5.
During operation of the fuel cell 1, the operation control unit 4 operates the cooling water circulation pump 12 and the hot water circulation pump 18 to perform hot water storage operation for storing hot water in the hot water tank 2. It is configured.
And in the hot water storage operation, the operation control unit 4 is based on the detection information of the heating temperature sensor 45, and the temperature of the hot water supplied to the hot water tank 2 is set at a preset target heating temperature (for example, 60 ° C.). In order to adjust the hot water circulation amount, the operation of the hot water circulation pump 18 is controlled.

In the hot water storage operation, the hot water extracted from the lower part of the tank is returned to the upper part of the tank by the circulating pump 18 for hot water, and the hot water in the hot water tank 2 is circulated through the hot water circulating circuit 17 and circulated through the hot water circulating circuit 17 as such. The hot water is heated with the cooling water from which the heat generated by the fuel cell 1 is recovered in the hot water storage heat exchanger 19, whereby hot water is stored in a state where a temperature stratification is formed in the hot water storage tank 2.
That is, the fuel cell 1, the cooling water circulation path 13, the cooling water circulation pump 12, the hot water circulation path 17, the hot water circulation pump 18, the hot water heat exchanger 19 and the like were taken out from the bottom of the tank. Hot water storage means for storing hot water in the hot water storage tank 2 is configured in such a manner that hot water is heated by the heat generated in the fuel cell 1 and then returned to the upper part of the tank.
Further, when the temperature detected by the tank bottom temperature sensor 47 becomes equal to or higher than a preset full determination temperature (for example, 55 ° C.) during execution of the hot water storage operation, the operation control unit 4 moves to the bottom of the hot water tank 2. In order to stop the hot water storage operation, the fuel cell 1 is stopped and the cooling water circulation pump 12 and the hot water circulation pump 18 are stopped, assuming that the amount of hot water stored in the hot water tank 2 is full. It is configured.

When a hot water tap or the like provided at the tip of the hot water supply path 16 is opened, the water in the hot water tank 2 is pushed up by the water pressure applied to the bottom of the tank by the water supply path 15 and sent to the hot water supply path 16. The detected flow rate of the hot water supply amount sensor 44 becomes equal to or higher than the set flow rate for determining the hot water supply state, and a hot water supply state in which hot water is supplied to the hot water consumption section through the hot water supply passage 16 is detected. A hot water supply state detecting means is configured.
When the hot water supply state is detected by the hot water supply amount sensor 44, the operation control unit 4 determines the temperature of the hot water detected by the inflow temperature sensor of the auxiliary heater 36 to the hot water supply temperature setting unit of the operation unit 48. When the hot water supply temperature sensor 43 is higher than the target hot water supply temperature, the operation of the hot water supply passage side adjustment valve 40 and the mixing water supply passage side adjustment valve 41 is controlled so that the temperature detected by the hot water supply temperature sensor 43 becomes the target hot water supply temperature. Is configured to do.
When the temperature of the hot water detected by the inflow temperature sensor of the auxiliary heater 36 is lower than the target hot water supply temperature, the operation control unit 4 determines that the detected temperature of the outflow temperature sensor of the auxiliary heater 36 is the target temperature. The combustion amount of the auxiliary heater 36 is controlled so as to reach the hot water supply temperature.

When the operation control unit 4 is instructed to start the heating operation by the heating switch of the operation unit 48, the operation control unit 4 switches the tank delivery switching valve 23 to the second tank delivery permitted state or the tank delivery stop state, and With the heating on-off valve 26 opened, the heat radiation operation circulation pump 22 and the heating circulation pump 30 are operated, and the detected temperature of the inflow temperature sensor of the auxiliary heater 36 is the heating set temperature ( For example, when the temperature is lower than 60 ° C., a heating operation is performed in which the combustion amount of the auxiliary heater 36 is controlled so that the temperature detected by the outflow temperature sensor becomes the set temperature for heating, and the heating operation is stopped by the heating switch. Is closed, the heating on-off valve 26 is closed, the heat radiation operation circulation pump 22 and the heating circulation pump 30 are stopped, and the heating operation is stopped.
In this heating operation, hot water is circulated while being heated by the auxiliary heater 36 through the heating circulation path R1, and a heating medium is circulated through the heating medium circulation path 29. The heating medium flowing through the heating medium circulation path 29 is heated by the hot water flowing through the circulation path R1, and the heat held by the heating medium is radiated at the heating terminal 28.

When the chasing operation is commanded by the chasing switch of the operation unit 48, the operation control unit 4 switches the tank sending switching valve 23 to the second tank sending allowance state or the tank sending stop state and performs the chasing operation. With the on-off valve 27 opened, the heat-dissipating operation circulation pump 22 and the bathtub circulation pump 34 are operated, and the detected temperature of the inflow temperature sensor of the auxiliary heater 36 is the set temperature for remedy. When the temperature is lower than (for example, 80 ° C.), a reheating operation for controlling the combustion amount of the auxiliary heater 36 is executed so that the temperature detected by the outflow temperature sensor becomes the reheating temperature.
Further, the operation control unit 4 is instructed to stop the chasing operation by the chasing switch of the operation unit 48 during execution of the chasing operation, or the return path portion of the bathtub hot water circulation path 33. When the temperature detected by the bathtub temperature sensor (not shown) provided at the temperature becomes equal to or higher than the set hot water temperature set by the hot water temperature setting unit of the operation unit 48, the remedy on-off valve 27 is closed, The recirculation operation is stopped by stopping the circulation pump 22 for heat dissipation operation and the circulation pump 34 for bathtub.
In this chasing operation, hot water circulates while being heated by the auxiliary heater 36 through the chasing circulation path R2, and hot water in the tub 32 circulates through the bath hot water circulation path 33, and the heat exchanger for chasing In 35, the hot water in the bathtub 32 flowing through the bathtub hot water circulation path 33 is heated by the hot water flowing through the memory circulation path R2, and the bathtub 32 is chased.

In the present invention, the operation control unit 4 is based on a determination operation process for switching the tank delivery switching three-way valve 23 to a tank delivery stop state and a change in the temperature of hot water in the hot water storage tank at the failure judgment timing. Thus, it is configured to execute a failure determination process for determining whether or not the tank delivery stop failure state.
In the determination operation process, it is an indispensable condition to switch the tank delivery switching three-way valve 23 to the tank delivery stop state. Therefore, in the following description, other than the tank delivery switching three-way valve 23 in the determination operation process. When the operation of the member is added, the operation for switching the tank delivery switching three-way valve 23 to the tank delivery stop state may be omitted.

In the first embodiment, the operation control unit 4 adds a set temperature increase width to the temperature of hot water in the hot water tank detected by the tank upper temperature sensor 46 at the start of the determination operation process. The temperature is set as the failure determination heating target temperature.
Then, the operation control unit 4 opens the tank bypass water supply on-off valve 21 and the heating on-off valve 26 and operates the heat radiation operation circulation pump 22 in the determination operation process, and the auxiliary heater 36. When the detected temperature of the inflow temperature sensor is lower than the target heating temperature for failure determination, the combustion amount of the auxiliary heater 36 is controlled so that the detected temperature of the outflow temperature sensor becomes the target heating temperature for failure determination. . That is, the heating target temperature of the auxiliary heater 36 is set to a failure determination heating target temperature that is higher than the temperature of the hot water in the hot water tank detected by the tank upper temperature sensor 46.

Further, in the failure determination process, the operation control unit 4 determines that the temperature of the hot water in the upper part of the hot water storage tank detected by the tank upper temperature sensor 46 increases during the failure determination set time for the failure determination temperature increase range. It is determined that there is a transmission stop failure state.
Incidentally, the set temperature increase width is set to 3 ° C., for example, the failure determination set time is set to 1 minute, and the failure determination temperature increase width is set to 1 ° C., for example.

That is, the operation control unit 4 is configured to open the tank bypass water supply opening / closing valve 21 and operate the heat radiation operation circulation pump 22 in the determination operation process, and in the failure determination process, Based on the temperature change of the hot water in the hot water storage tank, it is determined that the tank delivery stop failure state has occurred.
The operation control unit 4 is configured to heat the auxiliary heater 36 in the determination operation process. When the temperature of hot water in the upper part of the hot water storage tank rises in the failure determination process, the tank It is configured to determine that it is a transmission stop failure state.
Further, the operation control unit 4 controls the heating operation of the auxiliary heater 36 to heat the supplied hot water to a temperature higher than the temperature of the hot water in the upper part of the hot water tank in the determination operation process. It will be configured.

That is, when the determination operation process is executed, the hot water heated to the failure determination heating target temperature by the auxiliary heater 36 passes through the heating circulation path R1 and the heating circulation path portion 24 in the tank bypass water supply path 20 is obtained. The hot water supply side is circulated in the direction toward the hot water supply path side from the connection location of the hot water supply path, and in such a state that hot water is circulated through the heating circulation path R1, the tank delivery switching three-way valve 23 is When the tank delivery switching three-way valve 23 is not in a state of closing the hot water supply passage 16 in spite of being controlled so as to be switched to the tank delivery stop state, the heating circulation path portion in the tank bypass water supply passage 20 A part of the hot water that flows toward the hot water supply channel side through the portion of the hot water supply channel side from the connection point 24 passes through the tank delivery switching three-way valve 23, and the tank delivery switching three-way valve 23 in the hot water supply channel 16. Therefore, it is allowed to flow into the hot water tank side portion of the hot water tank 16, so that the hot water tank side portion of the hot water supply passage 16 is closed by the tank delivery switching three-way valve 23, the hot water tank 2. In the hot water tank circulation path R3 via the tank bypass water supply path 20, the hot water flows in the direction from the top to the bottom in the hot water tank. The temperature of the hot water in the hot water tank side or the hot water in the upper part of the hot water tank rises from the location to be closed.
Therefore, in the failure determination process, when the hot water in the upper part of the hot water storage tank rises during the failure determination temperature rise during the failure determination set time, it is determined that the tank delivery stop failure state is present.

That is, in the first embodiment, the heating circulation path portion 24 functions as an additional circulation path portion, and the auxiliary heater 36 functions as an additional heating means.
In addition, since the flow of the hot water is intentionally made to appear in the additional circuit portion in this way, it is possible to detect whether or not the tank delivery stop is in a failure state without waiting for the hot water supply to be used.

Further, the operation control unit 4 integrates the detected flow rate of the tank delivery amount sensor 42, and the integrated value of the detected flow rate of the tank delivery rate sensor 42 during the water quality improvement necessity determination period determines whether or not the water quality improvement is required. When it is less than the integrated flow rate for use, it is determined that it is the water quality improvement timing for improving the quality of the hot water in the hot water tank.
Incidentally, the water quality improvement necessity determination period is set to 96 hours, for example, and the water quality improvement necessity determination integrated flow rate is set to 200 liters, for example.
It should be noted that the tank feed amount sensor 42 is omitted, the detection information of the flow rate sensor provided in the hot water supply amount sensor 44 or the auxiliary heater 36 and detecting the flow rate of hot water flowing into the auxiliary heater 36, and the tank Based on the opening degree information of the delivery switching valve V1, the delivery amount from the hot water tank 2 may be obtained and the delivery amount may be integrated.

In the first embodiment, the failure determination timing is set to the water quality improvement timing, and when the operation control unit 4 reaches the water quality improvement timing, the determination operation process and the failure determination process are executed. When it is determined that the tank delivery stop failure state has not occurred, the hot water storage heating means H for heating the hot water in the hot water tank 2 heats the hot water in the entire hot water tank above the set temperature for improving the water quality. And when it is determined that the tank delivery stop failure state has occurred, the water quality improvement operation is not executed.
Incidentally, the preset temperature for water quality improvement is set to 60 ° C., for example.

  In the water quality improvement operation, the operation control unit 4 switches the tank delivery switching valve 23 to the second tank delivery permitted state, opens the heating on-off valve 26, and opens the tank bypass water supply on-off valve. When the heat-dissipating operation circulation pump 22 is operated with the valve 21 open, and the detected temperature of the inflow temperature sensor of the auxiliary heater 36 is lower than the heating target temperature for water quality improvement, the outflow temperature sensor is detected. The amount of combustion of the auxiliary heater 36 is controlled so that the temperature becomes the water quality improvement heating target temperature, and when the temperature detected by the tank bottom temperature sensor 47 becomes equal to or higher than the water quality improvement temperature, the heating opening and closing is performed. The valve 26 is closed, the heat radiation operation circulation pump 22 is stopped, and the water quality improvement operation is terminated.

That is, when the water quality improvement operation is executed, the hot water that is taken out from the lower part of the tank and flows through the tank bypass water supply path 20 and the auxiliary heater 36 at the connection portion of the heating circulation path portion 24 in the tank bypass water supply path 20. The hot water heated to the heating target temperature for water quality improvement and mixed with hot water flowing through the heating circuit portion 24 is mixed and mixed, and the mixed hot water flows through the tank bypass water supply channel 20 and is upstream of the hot water supply channel 16. The hot water in the hot water tank 2 is circulated through both the hot water tank circulation path R3 and the heating circulation path R1, and the hot water in the hot water tank 2 is heated. Become.
Incidentally, even if the hot water heated to the water quality improvement heating target temperature by the auxiliary heater 36 is mixed with the hot water of the hot water storage tank 2 taken out from the lower part of the tank, the water quality improvement heating target temperature is the hot water after mixing. Is set to a temperature at which the temperature becomes equal to or higher than the preset temperature for water quality improvement.
Accordingly, the hot water in the entire hot water storage tank is heated to a temperature higher than the set temperature for improving the water quality by the water quality improving operation, and the auxiliary heater 36 is configured to function as the hot water tank heating means H.

In addition to the tank delivery switching valve V1, a tank delivery suppression valve V3 that suppresses the delivery of hot water from the hot water storage tank 2 is provided, and the operation control unit 4 determines that it is in the tank delivery stop failure state. In order to suppress the delivery of hot water from the hot water storage tank 2, a failure countermeasure process for controlling the operation of the tank delivery suppression valve V3 is executed.
And in this 1st Embodiment, the said tank feed suppression valve V3 is comprised in the said mixing ratio adjustment valve V2 comprised by the said hot water supply path side adjustment valve 40 and the said mixing water supply path side adjustment valve 41, and the said operation control The unit 4 is configured to execute a process of closing the hot water supply path side adjustment valve 40 and fully opening the mixing water supply path side adjustment valve 41 as the failure countermeasure process.

That is, the operation control unit 4 executes a process for controlling the operation of the mixing ratio adjusting valve V2 so that the ratio of the hot water from the hot water tank 2 to the amount of mixed hot water is zero as the failure countermeasure process. It will be configured.
Incidentally, the failure countermeasure process may be configured to execute a process for controlling the operation of the mixing ratio adjusting valve V2 so that the ratio of the hot water from the hot water tank 2 to the amount of mixed hot water is substantially zero. . That is, when the mixing ratio control valve V2 is configured so that the ratio of hot water from the hot water tank 2 to the amount of mixed hot water cannot be zero, the hot water tank 2 relative to the amount of mixed hot water. It is only necessary to control the operation of the mixing ratio adjusting valve V2 so that the ratio of hot and cold water from the main body becomes approximately zero.

  Further, when the operation control unit 4 determines that the tank delivery stop failure state is not established, the heating operation is performed with the hot water supply path side adjustment valve 40 opened, and the tank delivery stop failure state is established. When it is determined that the heating operation is performed in a state where the hot water supply path side control valve 40 is closed, and when it is determined that the tank delivery stop failure state is not detected, the hot water supply path side control valve 40 is configured. The chasing operation is executed with the hot water supply side control valve 40 closed when the chasing operation is performed with the valve open and when it is determined that the tank delivery stop failure state has occurred. It is configured.

That is, each of the heating circulation path R1 and the memorial circulation path R2 is formed by using a part of a portion of the hot water supply path 16 on the downstream side of the place where the tank bypass water supply path 20 is connected. Corresponding to the internal circulation path R4, the heat radiation operation circulation pump 22 corresponds to the internal circulation circulation means P for circulating hot water through the internal circulation path R4, and the hot water supply path side control valve 40 is provided in the hot water supply path 16. It corresponds to an internal circulation path downstream on-off valve V4 that is provided in a portion downstream of the portion forming the internal circulation path R4 and opens and closes the hot water supply path 16.
Each of the heating operation and the memorial operation corresponds to an internal circulation operation.

  And the said operation control part 4 is comprised so that the internal circulation operation which operates the said circulation means P for internal circulation and circulates hot water through the said internal circulation path R4 based on the start command of internal circulation operation can be performed. When it is determined that the tank delivery stop failure state is not established, the internal circulation operation is performed with the internal circulation path downstream side open / close valve V4 opened, and the tank delivery stop failure state is determined. In this case, the internal circulation operation is performed with the internal circulation path downstream side open / close valve V4 closed.

Next, based on the flowchart shown in FIG.2 and FIG.3, the control operation of the hot water storage unit 3 by the said operation control part 4 is demonstrated.
As shown in FIG. 2, when it is determined that the water quality improvement timing has come, the operation control unit 4 executes determination control for determining whether or not the tank delivery stop failure state has occurred (steps # 1 and # 2).
As shown in FIG. 3, the operation control unit 4 performs the determination operation process and the failure determination process in the determination control, and determines that the tank delivery stop failure state is not present, the hot water storage tank 2 When the hot water supply operation for heating the hot water of the entire hot water storage tank to a temperature higher than the set temperature for water quality improvement is performed by the hot water storage tank heating means H for heating the hot water of the water, A failure countermeasure process is executed, and when the fuel cell 1 is in operation, a fuel cell operation stop process for stopping the operation of the fuel cell 1 is executed, and an abnormal lamp (not shown) provided in the operation unit 48 is turned on. An abnormality notification process is executed (steps # 21 to 28).

The operation control unit 4 continues the water quality improvement operation until the detected temperature of the tank bottom temperature sensor 47 becomes equal to or higher than the set temperature for improving water quality, and the detected temperature of the tank bottom temperature sensor 47 is set to the set temperature for improving water quality. If it becomes above, water quality improvement operation will be stopped.
In addition, when the operation control unit 4 determines that the tank delivery stop failure state is present in the failure determination process, the operation control unit 4 continues until the reset switch (not shown) provided in the operation unit 48 is pressed. The fuel cell 1 is configured not to be operated even when the operation start of the fuel cell 1 is instructed by the operation switch of the operation unit 48.

As shown in FIG. 2, when the operation control unit 4 determines that it is not the water quality improvement timing, the operation control unit 4 executes the hot water storage operation when the fuel cell 1 is in operation, and the heating switch of the operation unit 48 performs the heating operation. When the start is commanded, the hot water supply path side adjustment valve 40 is opened when the tank delivery stop failure state is not established, and then the heating operation is performed. When the tank delivery stop failure condition is established, the hot water supply path side adjustment valve is established. After the valve 40 is closed, the heating operation is executed. When the heating switch of the operation unit 48 is instructed to stop the heating operation, the heating operation is stopped (steps # 1, 3 to 11).
In addition, when the operation control unit 4 is instructed to start the chasing operation by the chasing switch of the operation unit 48, the operation control unit 4 opens the hot water supply path side control valve 40 when the tank feeding stop failure state is not established, After performing a chasing operation and closing the hot water supply path side control valve 40 when the tank delivery stop failure state, the chasing operation is performed, and the chasing operation is performed by the chasing switch of the operation unit 48. When the stop is instructed or when the stop of the chasing operation is instructed based on the detected temperature of the bathtub temperature sensor being equal to or higher than the set hot water temperature, the chasing operation is stopped (step # 12). To 18).

  In the first embodiment, inventions according to claims 1, 3, 5, 6, 7, 8, 12, and 13 are described.

[Second Embodiment]
In the following, the second embodiment will be described. This second embodiment describes another embodiment of the determination operation process and the failure determination process, and the overall configuration of the cogeneration system is the same as that of the first embodiment. Since it is the same as FIG. 1 described in FIG. 1, the failure determination process will be mainly described.
In the second embodiment, the operation control unit 4 switches the tank delivery switching three-way valve 23 to the tank delivery stop state and opens the tank bypass water supply opening / closing valve 21 in the determination operation process. When the detected flow rate of the hot water supply amount sensor 44 is equal to or higher than the set flow rate for determining the hot water supply state and the hot water supply state is detected in the failure determination process, the tank upper temperature sensor 46 detects the hot water supply state. When the temperature of the hot water in the upper part of the hot water storage tank decreases during the failure determination set time, the failure determination temperature drop is reduced, and the tank delivery stop failure state is determined.
Incidentally, the failure determination temperature decrease width is set to 1 ° C., for example.

Also in the second embodiment, as in the first embodiment, the failure determination timing is set to the water quality improvement timing. However, when the operation control unit 4 reaches the water quality improvement timing, After performing the water quality improvement operation in which the hot water in the entire hot water tank is heated to a temperature higher than the set temperature for improving the water quality by the hot water tank heating means H for heating the hot water in the hot water tank 2, the discrimination operation process and the failure discrimination process are performed. It differs from the above embodiment in that it is configured to execute.
Since the specific control configuration in the water quality improvement operation is the same as that in the first embodiment, description thereof will be omitted. That is, also in the second embodiment, the auxiliary heater 36 is configured to function as the hot water tank heating means H.

Next, the control operation of the hot water storage unit 3 by the operation control unit 4 will be described, but the overall control operation is the same as the control operation described based on the flowchart shown in FIG. 2 in the first embodiment. The description will be omitted, and the control operation in the discrimination control will be described based on the flowchart shown in FIG.
The operation control unit 4 continues the water quality improvement operation until the temperature detected by the tank bottom temperature sensor 47 becomes equal to or higher than the set temperature for water quality improvement, and the temperature detected by the tank bottom temperature sensor 47 is equal to or higher than the set temperature for water quality improvement. Then, the water quality improvement operation is terminated, the determination operation process and the failure determination process are executed, and if it is determined that the tank delivery stop failure state is detected, the failure countermeasure process is executed, and the fuel cell When the fuel cell 1 is in operation, a fuel cell operation stop process for stopping the operation of the fuel cell 1 is executed, an abnormality notification process for turning on an abnormality lamp (not shown) provided in the operation unit 48 is executed, and the process returns. If it is determined that the tank delivery stop failure state has not occurred, the process directly returns (steps # 31 to 38).

  In the second embodiment, the inventions according to claims 2 and 14 are mainly described.

[Third Embodiment]
Hereinafter, the third embodiment will be described. This third embodiment is different from the mixing ratio adjustment valve V2 and the tank delivery suppression valve V3, and the distinction between the determination operation process, the failure determination process, and the failure countermeasure process. This embodiment will be described.
As shown in FIG. 5, in the third embodiment, the mixing ratio adjustment valve V <b> 2 is connected to the hot water supply upstream port to which the hot water storage tank side portion of the hot water supply channel 16 is connected, and the hot water consumption unit side of the hot water supply channel 16. The mixing ratio adjusting three-way valve 49 includes three ports: a hot water supply channel downstream side port to which the portion is connected and a water supply channel port to which the mixing water supply channel 37 is connected.
That is, the mixing ratio adjusting three-way valve 49 adjusts the opening degree of each of the hot water supply upstream port and the water supply port, thereby supplying water supplied through the mixing water supply 37 as the downstream water supply channel. The mixing ratio with the hot water from the hot water tank 2 supplied through the hot water supply passage 16 is adjusted.
Incidentally, the three-way valve 49 for adjusting the mixing ratio has a structure in which the hot water supply path upstream port cannot be closed, that is, a structure in which the hot water supply path 16 cannot be closed.

In the third embodiment, the operation control unit 4 opens the tank bypass water supply on-off valve 21 and the heating on-off valve 26 and operates the heat radiation operation circulation pump 22 in the determination operation process. In the failure determination process, the temperature of the hot water in the hot water tank detected by the tank upper temperature sensor 46 is detected by the inflow temperature sensor of the auxiliary heater 36. When the temperature of the hot water in the hot water storage tank detected by the tank upper temperature sensor 46 decreases during the failure determination set time, the tank delivery is stopped. It is comprised so that it may discriminate | determine that it is a failure state.
That is, in the third embodiment, the heating circuit portion 24 is made to function as an additional circuit portion, the auxiliary heater 36 is made to function as an additional heating means, and the heating circuit R1 is made to function as an additional circuit. It is configured.
In short, the hot water stored in the hot water tank 2 is less likely to become low temperature due to the heat retaining function of the hot water tank 2, whereas the hot water in the additional circulation circuit is easy to cool and low temperature. The state in which the temperature of the hot water in the hot water storage tank side or the hot water in the upper part of the hot water storage tank is higher than the temperature of the hot water in the additional circulation path with respect to the location closed by the tank delivery switching valve V1 in the hot water supply path 16 In this third embodiment, energy consumption can be suppressed by determining whether or not the tank delivery is stopped in such a state.

The operation control unit 4 controls the operation of the mixing ratio adjusting three-way valve 49 so as to minimize the opening degree of the hot water supply path upstream port and maximize the opening degree of the water supply path side port in the failure countermeasure process. It is configured.
That is, in the third embodiment, the tank feed suppression valve V3 is configured by the mixing ratio adjusting three-way valve 49 as the mixing ratio adjusting valve V2.
Then, the operation control unit 4 suppresses the delivery of hot water from the hot water tank 2 and supplies water to the hot water supply passage 16 in the mixing water supply passage 37 as a downstream water supply passage as the failure countermeasure processing. It is comprised so that the process which controls the action | operation of the tank delivery suppression valve V3 may be performed.
Further, the operation control unit 4 operates the mixing ratio adjusting valve V2 to minimize the ratio of hot water from the hot water tank 2 and maximize the ratio of water supplied through the mixing water supply path 37 as the failure countermeasure process. It is comprised so that the process which controls may be performed.

  Since the control operation of the hot water storage unit 3 by the operation control unit 4 is the same as the control operation described based on the flowcharts shown in FIGS. 2 and 3 in the first embodiment, the description is omitted.

  In the third embodiment, the inventions according to claims 3, 4, 9, and 10 are mainly described.

[Fourth Embodiment]
Hereinafter, the fourth embodiment will be described. This fourth embodiment shows another embodiment of the failure countermeasure processing, and the determination operation processing and the failure determination processing are performed in the first to third embodiments. Since the overall configuration of the cogeneration system is the same as that of FIG. 1 described in the first embodiment, the failure countermeasure processing will be mainly described.
In the fourth embodiment, a mixed water supply path 37 serving as a downstream water supply path that supplies water to a location downstream of the hot water supply channel 16 where the tank bypass water supply channel 20 is connected, and the mixed water supply channel 37. Failure countermeasure processing is performed using a mixed water supply path side adjustment valve 41 as a water supply amount adjustment valve that adjusts the amount of water supplied through.
That is, when the operation control unit 4 determines that the tank delivery stop failure state is present as a failure countermeasure process, the tank delivery switching valve V1 is maintained in the tank delivery stop state, and the opening of the mixed water supply path side control valve 41 is maintained. Therefore, the operation of the water supply amount adjusting valve is controlled to adjust the maximum value or the maximum value.

Thus, when it is determined that the tank delivery stop failure state has occurred, the opening of the mixed water supply path side control valve 41 is adjusted to the maximum or substantially maximum, and the tank bypass water supply path 20 in the hot water supply path 16 through the mixed water supply path 37. A large amount of water is supplied to a location downstream of the location where the water supply is connected, and the hot water from the hot water storage tank 2 passes through the tank delivery switching valve V1 in the tank delivery stop state, and the bypass water supply path in the hot water supply path 16 Even if it leaks to the downstream side of the location where 20 is connected, the quality of the hot water supplied through the hot water supply passage 16 can be improved by the dilution action by the large amount of water supplied through the mixed water supply passage 37. It can be done.
In the fourth embodiment, the hot water supply path side control valve 40 can be omitted. However, when the hot water supply path side control valve 40 is present, the opening of the hot water supply path side control valve 40 is fully closed or substantially closed. By fully closing it, it is possible to more reliably suppress the supply of hot water that may have deteriorated water quality to the hot water consumption section.

[Another embodiment]
Next, another embodiment will be described.
(A) Instead of the tank upper temperature sensor 46, a tank delivery switching valve upstream temperature sensor for detecting the temperature of the hot water in the hot water storage tank side of the hot water supply passage 16 relative to the location closed by the tank delivery switching three-way valve 23. Is provided.
In the first embodiment, in the failure determination process, the temperature of the hot water in the hot water tank detected by the tank upper temperature sensor 46 is increased during the failure determination set time period during the failure determination set time. Then, instead of the configuration for determining that there is a tank delivery stop failure state, if the temperature of the hot water detected by the temperature sensor on the upstream side of the tank delivery switching valve increases during the failure discrimination set time, You may comprise so that it may discriminate | determine that it is a transmission stop failure state.
In the third embodiment, in the failure determination process, the temperature of hot water in the hot water tank detected by the tank upper temperature sensor 46 is used for heating detected by the inflow temperature sensor of the auxiliary heater 36. When the temperature of the hot water in the circulation path R1 is higher than the temperature of the hot water in the hot water storage tank detected by the tank upper temperature sensor 46, the tank is replaced with a configuration in which it is determined that there is a tank delivery stop failure state. When the temperature of the hot water detected by the upstream temperature sensor of the delivery switching valve is higher than the temperature of the hot water in the heating circuit R1 detected by the inflow temperature sensor of the auxiliary heater 36, the upstream side of the tank delivery switching valve When the temperature of the hot water detected by the temperature sensor decreases, it may be determined that the tank delivery stop failure state has occurred.

(B) In the second embodiment, when the hot water supply state is detected when the detected flow rate of the hot water supply amount sensor 44 becomes equal to or higher than the set flow rate for hot water supply state determination in the failure determination process, the tank upper temperature sensor 46 is detected. In place of the configuration in which the temperature of the hot water in the upper part of the hot water storage tank detected at the time of the failure determination temperature drop decreases during the failure determination setting time, the tank delivery stop sensor 44 is replaced with a configuration that determines that the tank delivery stop failure state has occurred. When the detected flow rate becomes equal to or higher than the set flow rate for determining the hot water supply state and the hot water supply state is detected, the temperature of the hot water at the bottom of the hot water tank detected by the tank bottom temperature sensor 47 is between the set times for failure determination. It may be configured to determine that the tank delivery stop failure state is present when the failure determination temperature drop is reduced.

(C) The specific configuration of the tank delivery suppression valve V3 is not limited to the configuration illustrated in each of the first to third embodiments. For example, the mixing ratio adjustment valve V3 and the high-temperature hot water avoidance valve 38 You may comprise by.
In this case, the operation control unit 4 controls the operation of the mixing ratio adjustment valve V3 so as to minimize or substantially minimize the ratio of hot water from the hot water tank 2 as a failure countermeasure process, and the high temperature hot water avoidance valve 38 is In order to open the valve, a process for controlling the operation of the high temperature hot water avoidance valve 38 is executed.
Specifically, when this different embodiment is applied to each of the first and second embodiments described above, the hot water supply path side adjustment valve 40 constituting the mixing ratio adjustment valve V3 is configured to be closed, and this When another embodiment is applied to the third embodiment, the mixing ratio adjusting three-way valve 49 as the mixing ratio adjusting valve V3 is controlled to minimize the opening degree of the upstream port of the hot water supply channel. Will do.

(D) The specific configuration of the tank delivery switching valve V1 is not limited to the configuration exemplified in the first to third embodiments, that is, the tank delivery switching three-way valve 23. .
For example, as shown in FIG. 6, in place of the tank delivery switching three-way valve 23, a hot water supply path opening / closing valve that opens and closes a portion of the hot water supply path 16 closer to the hot water storage tank than the connection place of the tank bypass water supply path 20. 50 and the tank feed switching valve V <b> 1 may be configured by the hot water supply path opening / closing valve 50 and the tank bypass water supply path opening / closing valve 21. In the case of this configuration, the hot water supply passage opening / closing valve 50 is opened and closed to switch between the tank delivery permission state and the tank delivery stop state.
In addition, as shown in FIG. 7, instead of the tank delivery switching three-way valve 23, a water supply path opening / closing valve that opens and closes a portion of the water supply path 15 that is closer to the hot water storage tank than the branch bypass water supply path 20. 51, and the tank delivery switching valve V <b> 1 may be configured by the water supply path opening / closing valve 51 and the tank bypass water supply path opening / closing valve 21. In the case of this configuration, the tank delivery permissible state and the tank delivery stop state are switched by opening / closing the water supply passage opening / closing valve 51.
In the case of this configuration, the hot water in the hot water storage tank side portion of the hot water supply path 16 is closer to the hot water storage tank side than the connection place of the tank bypass water supply path 20 in the hot water supply path 16. This means hot water in the hot water supply channel located in the area.

(E) In each of the first to third embodiments, in the water quality improvement operation, the auxiliary heater 36 is configured to heat the hot water in the hot water tank 2, and the auxiliary heater 36 stores hot water. Although the case where the tank heating means H is configured is illustrated, the hot water storage heat exchanger 19 is configured to heat the hot water in the hot water storage tank 2 using the exhaust heat of the fuel cell 1, and the hot water storage heat exchanger 19 The hot water storage tank heating means H may be configured.

(F) When the supplied hot water is heated by the auxiliary heater 36 in the discrimination operation process, in the third embodiment, in the hot water tank upper part detected by the tank upper temperature sensor 46. Although illustrated about the case where it comprised so that it might heat to the temperature higher than the temperature of the hot water of water, you may comprise so that it may heat to temperature higher than target heating temperature (for example, 60 degreeC).

(G) In each of the first to third embodiments described above, the case where the failure determination timing is set to the water quality improvement timing is illustrated, but the specific timing of the failure determination timing is set to various timings. be able to.
For example, the failure determination timing may be set every set period (for example, 96 hours).
Further, the operation control unit 4 is configured to determine that the failure determination timing is reached when the heating operation is commanded by the heating switch of the operation unit 48, so that the determination operation process and the failure determination are performed prior to the heating operation. You may comprise so that a process may be performed.
The determination operation process and the failure determination process in this case are the same as in the first embodiment.
Further, the operation control unit 4 is configured to determine that the failure determination timing has been reached when the tracking operation is instructed by the tracking switch of the operation unit 48, so that the determination operation process is performed prior to the tracking operation. In addition, the failure determination process may be executed.
The determination operation process and the failure determination process in this case are the same as in the first embodiment.
That is, in this case, the memorial circuit portion 25 functions as an additional circuit portion, and the auxiliary heater 36 functions as an additional heating means.

(H) The operation control unit 4 is configured to open the tank bypass water supply opening / closing valve 21 and the remedy opening / closing valve 27 and to operate the heat radiation operation circulation pump 22 in the determination operation process. When the temperature of the hot water in the upper part of the hot water tank detected by the tank upper temperature sensor 46 is higher than the temperature of the hot water in the recirculation circuit R2 detected by the inflow temperature sensor of the auxiliary heater 36, When the temperature of the hot water in the upper part of the hot water storage tank detected by the upper temperature sensor 46 is lowered, it may be determined that it is a tank delivery stop failure state.
That is, in this other embodiment, the remedy circuit portion 25 functions as an additional circuit portion, the auxiliary heater 36 functions as an additional heating means, and the remedy circuit R2 functions as an additional circuit. It will be configured as follows.

(L) The failure determination process described in the second embodiment, that is, when the hot water temperature is detected by the hot water supply amount sensor 44 and the temperature of the hot water in the upper part of the hot water storage tank is lowered, the tank delivery stop failure state is assumed. The failure determination process in the determination mode is performed by the determination control described in the first embodiment, that is, the determination operation process and the failure determination process are performed when the water quality improvement timing comes, and it is determined that the failure is not in the tank delivery stop failure state. In such a case, the water quality improvement operation may be performed, and when it is determined that the tank delivery stop failure state has occurred, the control may be performed in the discrimination control in a form in which the water quality improvement operation is not executed.
Further, the determination operation process and the failure determination process described in the third embodiment, that is, a mode in which the tank bypass water supply opening / closing valve 21 and the heating opening / closing valve 26 are opened and the heat radiation operation circulation pump 22 is operated. When the temperature of the hot water in the upper part of the hot water storage tank is lowered when the temperature of the hot water in the upper part of the hot water tank is higher than the temperature of the hot water in the heating circuit R1 The failure determination processing in the form of determining that there is, the determination control described in the second embodiment, that is, the water quality improvement operation is executed at the timing of water quality improvement, and then the operation operation for determination and the failure determination processing are executed. You may comprise so that it may implement in the discrimination control in a form.

(Nu) Although the fuel cell 1 is applied in the first to third embodiments as the combined heat and power supply apparatus, there are various other configurations such as a configuration in which a generator is driven by a gas engine, for example. Can be applied.

(L) In each of the first to third embodiments described above, the present invention is applied to a cogeneration system, and heat generated from a combined heat and power supply device is used as a heat source for hot water storage means for storing hot water in the hot water tank 2. However, various heat sources can be used as the heat source of the hot water storage means.
For example, the fuel cell 1, the inverter 5, the electric heater 11, the cooling water circulation path 13, the cooling water circulation pump 12, the hot water circulation path 17, the hot water circulation pump 18, the hot water storage heat exchanger 19, and the like associated therewith are omitted. Thus, the auxiliary heater 36 may be configured as a heat source for the hot water storage means.
That is, the hot water storage operation of storing hot water in the hot water storage tank 2 is performed by performing the same control as the water quality improvement operation described in the first embodiment.
In this case, the hot water supply path 16, the tank bypass water supply path 20, the heating circulation path portion 24, the tank bypass water supply path opening / closing valve 21, the tank delivery switching three-way valve 23, the heating opening / closing valve 26, the heat radiation circulation pump 22 and the auxiliary The hot water storage means is configured by using the heater 36 or the like.
Further, as a heat source for the hot water storage means, an electric heater may be used, an electric heat pump driven by an electric motor, or an engine driven heat pump driven by an engine.

The block diagram which shows the whole structure of the hot water storage type hot water supply apparatus which concerns on 1st Embodiment. The figure which shows the flowchart of the control action in the hot water storage type hot water supply apparatus which concerns on 1st Embodiment. The figure which shows the flowchart of the control action in the hot water storage type hot water supply apparatus which concerns on 1st Embodiment. The figure which shows the flowchart of the control action in the hot water storage type hot water supply apparatus which concerns on 2nd Embodiment. The block diagram which shows the whole structure of the hot water storage type hot water supply apparatus which concerns on 3rd Embodiment. The block diagram which shows the whole structure of the hot water storage type hot water supply apparatus which concerns on another embodiment. The block diagram which shows the whole structure of the hot water storage type hot water supply apparatus which concerns on another embodiment.

Explanation of symbols

2 Hot water storage tank 4 Operation control means 15 Water supply path 16 Hot water supply path 20 Tank bypass water supply path 21 Tank bypass water supply opening / closing valve 22 Additional circulation means 23 Three-way valve for tank delivery switching (tank delivery switching valve)
24, 25 Additional circulation path portion 36 Additional heating means 37 Downstream water supply path 38 High temperature hot water avoidance valve 39 High temperature hot water avoidance water supply path 41 Water supply amount adjustment valve 44 Hot water supply state detection means H Hot water tank heating means P Circulation means for internal circulation R1, R2 Additional circulation path R4 Internal circulation path V1 Tank delivery switching valve V2 Mixing ratio adjustment valve V3 Tank delivery suppression valve V4 Internal circulation path downstream opening / closing valve

Claims (15)

A hot water storage tank in which water is supplied through a water supply path connected to the bottom and hot water is sent out through a hot water supply path connected to the top;
A tank detour water supply path that detours the hot water tank and supplies water to the hot water supply path;
A tank delivery switching valve that is switchable between a tank delivery permitting state in which the hot water supply path is opened and hot water delivery from the hot water storage tank is permitted, and a tank delivery stop state in which the hot water supply path is closed and the tank bypass water supply path is opened. ,
A hot water storage type hot water supply apparatus provided with an operation control means for controlling operation,
When the operation control means reaches the failure determination timing, the hot water storage is more than the operation operation for determination for switching the tank delivery switching valve to the tank delivery stop state and the location closed by the tank delivery switching valve in the hot water supply channel. A hot water storage type hot water supply apparatus configured to execute a failure determination process for determining whether or not a tank delivery stop failure state is based on a temperature change of hot water in a tank side portion or hot water in the hot water storage tank. Hot water supply state detection means for detecting a hot water supply state in which hot water is supplied to the hot water consumption section through the hot water supply path is provided,
When the operation control means detects that the hot water supply state is detected by the hot water supply state detection means in the failure determination process, the temperature of the hot water in the upper part of the hot water storage tank or in the bottom part of the hot water storage tank decreases. The hot water storage type hot water supply apparatus according to claim 1, wherein the hot water storage type hot water supply apparatus is configured to determine that the state is a stop failure condition. The tank bypass water supply channel is branched from the water supply channel and connected to the hot water supply channel;
The tank detour water supply path has a tank detour water supply opening / closing valve that opens and closes the tank detour water supply path, and an additional circulation means that causes hot water to flow toward the hot water supply path. Is located in the state,
A portion of the hot water supply channel that is further away from the hot water storage tank than a portion to which the tank bypass water supply channel is connected; a portion of the tank bypass water supply channel that is between the tank bypass water supply channel opening / closing valve and the additional circulation means; An additional circuit portion connected to the
The operation control means is configured to open the tank bypass water supply opening / closing valve and operate the additional circulation means in the determination operation process, and in the failure determination process, the tank in the hot water supply path. It is configured to determine whether or not the tank delivery stop failure state is based on the temperature change of the hot water in the hot water tank side portion or the hot water in the hot water tank relative to the location closed by the delivery switching valve. The hot water storage type hot water supply apparatus according to claim 1.   The temperature of the hot water in the hot water tank side or in the upper part of the hot water tank is higher than the temperature of the hot water in the hot water tank than the location where the operation control means is closed by the tank delivery switching valve in the hot water supply path in the failure determination process. An additional circulation path that passes through a circulation path portion, a portion on the hot water supply path side of the connection place of the additional circulation path portion in the tank bypass water supply path, and a downstream portion of the connection area of the tank bypass water supply path in the hot water supply path When the temperature of hot water in the hot water storage tank is lower than the location closed by the tank delivery switching valve in the hot water supply path or when the temperature of hot water in the upper part of the hot water storage tank decreases, The hot water storage type hot water supply apparatus according to claim 3, wherein the hot water storage type hot water supply apparatus is configured to determine that it is in a stop failure state. In the hot water supply path, an additional heating means for heating the hot water supplied to the hot water supply path portion located between the connection location to which the tank bypass water supply channel is connected and the connection location to which the additional circulation path portion is connected. Is provided,
The operation control means is configured to heat the additional heating means in addition to operating the additional circulation means in the determination operation processing, and in the failure determination processing, the operation control means is configured to operate the additional heating means in the hot water supply path. Claims that when the temperature of the hot water in the hot water storage tank side or the hot water in the upper part of the hot water storage tank rises from the location closed by the tank delivery switching valve, it is determined that the tank delivery stop failure state has occurred. Item 4. A hot water storage type hot water supply apparatus according to item 3.   In the operation process for determination, the operation control means sets the heating target temperature of the additional heating means to a portion of the hot water tank or hot water stored in a portion closer to the hot water tank than a position closed by the tank delivery switching valve in the hot water supply passage. The hot water storage type hot water supply apparatus according to claim 5, wherein the hot water storage apparatus is configured to be set at a temperature higher than the temperature of hot water in the upper part of the tank. In addition to the tank delivery switching valve, a tank delivery suppression valve that suppresses the delivery of hot water from the hot water storage tank is provided,
When it is determined that the operation control means is in the tank delivery stop failure state, it is configured to execute a failure countermeasure process for controlling the operation of the tank delivery suppression valve to suppress delivery of hot water from the hot water storage tank. The hot water storage type hot water supply apparatus according to any one of claims 1 to 6. A downstream water supply channel for supplying water to a location downstream from the location where the tank bypass water supply channel in the hot water supply channel is connected;
A mixing ratio control valve capable of adjusting a mixing ratio of water supplied through the downstream water supply passage and hot water from the hot water tank supplied through the hot water supply passage;
The tank delivery suppression valve is composed of the mixing ratio adjustment valve,
The operation control means executes a process for controlling the operation of the mixing ratio adjusting valve so that the ratio of the hot water from the hot water tank to the amount of mixed hot water is 0 or substantially 0 as the failure countermeasure process. The hot water storage type hot water supply apparatus according to claim 7, which is configured as follows. A downstream water supply channel is provided for supplying water to a location downstream from the location where the tank bypass water supply channel in the hot water supply channel is connected;
The tank delivery suppression valve is configured to be able to intermittently supply water to the hot water supply passage by the downstream water supply passage,
The operation control means controls the operation of the tank delivery suppression valve to suppress the delivery of hot water from the hot water storage tank and supply water to the hot water supply path in the downstream water supply path as the failure countermeasure process. The hot water storage type hot water supply apparatus according to claim 7, wherein the hot water storage apparatus is configured to be executed. There is provided a mixing ratio control valve capable of adjusting the mixing ratio of the water supplied through the downstream water supply channel and the hot water from the hot water storage tank supplied through the hot water supply channel, and the mixing ratio control valve supplies the tank. A suppression valve is configured,
The operation control means, as the failure countermeasure process, minimizes or substantially minimizes the ratio of hot water from the hot water tank and maximizes or substantially maximizes the ratio of water supplied through the downstream water supply channel. The hot water storage type hot water supply apparatus according to claim 9, wherein the hot water storage apparatus is configured to execute processing for controlling operation of the control valve. A mixing ratio adjusting valve capable of adjusting a mixing ratio of water supplied through the downstream water supply passage and hot water from the hot water tank supplied through the hot water supply passage;
High temperature equipped with a high temperature hot water avoidance valve that supplies water to a location downstream of the location where the downstream water supply channel is connected in the hot water supply channel, and opens in a state where power for opening / closing operation is not supplied There is a hot water avoidance water supply channel,
The tank delivery suppression valve is composed of the mixing ratio adjustment valve and the high temperature hot water avoidance valve,
The operation control means controls the operation of the mixing ratio adjustment valve to minimize or substantially minimize the ratio of hot water from the hot water tank and opens the high temperature hot water avoidance valve as the failure countermeasure process. The hot water storage type hot water supply apparatus according to claim 9, which is configured to execute processing for controlling the operation of the high temperature hot water avoidance valve as much as possible. A downstream water supply channel for supplying water to a location downstream from the location where the tank bypass water supply channel in the hot water supply channel is connected;
A water supply amount adjustment valve for adjusting the amount of water supplied through the downstream water supply channel,
When the operation control means determines that the tank delivery stop failure state, the tank delivery switching valve is maintained in the tank delivery stop state, and the opening of the water supply amount adjustment valve is maximized or substantially maximized. The hot water storage type hot water supply apparatus according to any one of claims 1 to 6, wherein a failure countermeasure process for controlling an operation of the water supply amount adjusting valve to be adjusted is executed. An internal circulation path formed by using a part of the downstream portion of the hot water supply path where the tank bypass water supply path is connected;
An internal circulation means for circulating hot water through the internal circulation path is provided,
An internal circulation path downstream on-off valve that opens and closes the hot water supply path is provided in a portion on the downstream side of the part forming the internal circulation path in the hot water supply path,
The operation control means is configured to execute an internal circulation operation of operating the internal circulation circulation means to circulate hot water through the internal circulation path based on an internal circulation operation start command, and When it is determined that the tank delivery stop failure state has not occurred, the internal circulation operation is performed with the internal circulation path downstream side open / close valve opened, and when it is determined that the tank delivery stop failure state has occurred, The hot water storage type hot water supply apparatus according to any one of claims 1 to 12, wherein the internal circulation operation is performed in a state in which a circulation path downstream side on-off valve is closed. The failure determination timing is set to a water quality improvement timing for improving the quality of hot water in the hot water tank,
When the operation control means performs the determination operation process and the failure determination process at the timing of improving the water quality, and determines that the tank delivery stop failure state is not present, the hot water storage for heating the hot water in the hot water storage tank When the tank heating means performs a water quality improvement operation for heating the hot water in the entire hot water storage tank to a temperature equal to or higher than the set temperature for water quality improvement, and if it is determined that the tank delivery stop failure state, the water quality improvement operation is executed. The hot water storage type hot water supply apparatus according to any one of claims 1 to 13, wherein the hot water storage apparatus is configured not to be used. The failure determination timing is set to a water quality improvement timing for improving the quality of hot water in the hot water tank,
When the operation control means reaches the water quality improvement timing, the water storage tank heating means for heating the hot water in the hot water tank performs a water quality improvement operation for heating the hot water in the entire hot water tank to a temperature higher than the set temperature for water quality improvement. The hot water storage type hot water supply apparatus according to any one of claims 1 to 4 and 7 to 13, wherein the determination operation process and the failure determination process are executed.

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