JP2007071411A - Hot water storage type water heater - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To improve safety and COP by using the water of intermediate temperature preferentially and inhibiting outflow of contamination in power fail recovery. <P>SOLUTION: When power fail recovery is confirmed by a power fail detecting portion 139, a first mixing valve 120 is kept in a hot water-side full open state, mixing control thereafter is inhibited, and the control inhibition state of the first mixing valve 120 is released to recover a normal operation, when the completion of full boiling-up operation is confirmed. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a hot water storage type hot water supply apparatus, and particularly to hot water mixing control using an electric mixing valve.

  Conventionally, this type of hot water storage type hot water supply device stores hot water heated by a heat pump circuit in a stratified state from the upper part of the hot water storage tank, and the hot water stored in the hot water storage tank is taken out from the upper hot water discharge pipe and mixed with the water supplied from the water supply pipe. Then, it is adjusted to a predetermined hot water temperature and supplied to a load side such as a hot water supply terminal. Further, in recent years, hot water storage type hot water supply devices having a function of using this hot water storage for bathing and heating are drawing attention. However, in this case, the hot water whose temperature has dropped after being used for bathing or heating is collected again in the hot water storage tank, so the hot water inside the hot water tank is called halfway hot water below the upper hot water. A large amount of hot and cold water will be stored. When the whole amount boiling operation is performed in a state where the medium-temperature water is stored, the heating operation of the heat pump cycle is performed in a state where the incoming water temperature to the heat pump circuit is high. Become.

Therefore, as disclosed in Patent Document 1, as disclosed in Patent Document 1, an intermediate temperature water outlet is provided in the middle portion of the hot water storage tank, and the intermediate temperature water extracted from the outlet and the high temperature water extracted from the upper outlet pipe are disposed. A predetermined hot water temperature is ensured by mixing, and the mixed water and water supplied from a water supply pipe are mixed to obtain hot water at a set temperature with high accuracy. According to this method, the medium-temperature water can be actively taken out, so that low-temperature water can be secured below the hot water tank, and the use of high-temperature water above the hot water tank can be minimized. It is possible to suppress the boiling operation of the COP and the phenomenon of running out of hot water.
JP 2003-240342 A

  However, according to the above conventional configuration, in the hot water supply apparatus using the heat pump circuit, by providing means for using the medium temperature water preferentially in order to eliminate the influence on the boiling performance of the medium temperature water, Can secure low-temperature water, minimize the use of high-temperature water above the hot water storage tank, and can control the boiling operation of high COP and the phenomenon of running out of hot water. Although it is an extremely effective means of using hot water in the equipment, if the use of hot water in the hot water tank stagnates for a long time due to a power failure, etc., and the temperature of the hot water in the hot water tank decreases, breeding of germs In particular, there is a risk of harm to the human body when Legionella is propagated. This Legionella bacterium is active in a range of hot water temperature of 25 ° C. to 50 ° C., and this hot water temperature range is a phenomenon that is likely to occur in the lower part of the hot water storage tank in the power outage state. In such a state, if hot water is supplied using the means for using medium-temperature water, the proliferated bacteria such as Legionella bacteria are actively supplied to the user terminal, which has a problem in terms of hygiene.

  The present invention solves the above-described conventional problems, and provides a hot water mixing control method capable of preferentially using medium-temperature water, which is an extremely effective means for using hot water in a heat pump type hot water supply apparatus, while preventing power outages and the like. The purpose of the present invention is to provide a hot water storage type hot water supply device that ensures safety when the use of hot water is stagnant.

In order to solve the above-mentioned conventional problems, the hot water storage type hot water supply apparatus of the present invention stores hot water heated using a heat pump circuit in a stratified state from the upper part of the tank and supplies desired hot water to the terminal side using the hot water. A hot water storage pipe for taking out hot water from the upper part of the tank, an intermediate temperature hot water pipe for taking out hot water from a substantially intermediate part of the tank, and a first mixing valve for mixing hot water from the hot water pipe and the intermediate temperature hot water pipe. A use side mixing valve that mixes hot water from the first mixing valve and water from the water supply pipe and supplies hot water at a predetermined temperature to the terminal side, and valve opening control of the first mixing valve and the use side mixing valve. A hot water storage type hot water supply device that sets a time zone for performing a full-boiling operation, and sets a hot-water boiling operation when it is determined that the amount of hot water is insufficient. A power failure occurred and then recovered When, in which so as to prohibit the control of the first mixing valve.

  According to the above invention, as a hot water use mode at the time of power failure recovery after the hot water usage in the hot water storage tank has been stagnated for a long time due to a power failure, the first mixing valve is controlled so as not to supply hot water from the intermediate temperature hot water pipe. Even if hot water in the hot water tank stagnates during the power outage and the temperature drops in the lower part of the hot water tank and miscellaneous bacteria such as Legionella propagates, the hot water in the upper part of the hot water tank The hot water can be supplied without being affected by various bacteria.

  The hot water storage type hot water supply apparatus of the present invention provides a hot water mixing control method capable of preferentially using medium hot water, which is an extremely effective means as a hot water use form of a heat pump type hot water supply apparatus, while the use of hot water is stagnant due to a power failure or the like. Therefore, it is possible to provide a hot water storage type hot water supply apparatus that ensures safety when the operation is performed.

  A first aspect of the present invention is a hot water storage type hot water supply apparatus that stores hot water heated using a heat pump circuit in a stratified state from the upper part of the tank and supplies the desired hot water to the terminal side using the hot water. From a hot water pipe, an intermediate temperature hot water pipe that takes out hot water at a substantially middle part of the tank, a first mixing valve that mixes hot water from the hot water pipe and the intermediate temperature hot water pipe, and hot water from the first mixing valve and a water supply pipe A use-side mixing valve that mixes water and supplies hot water at a predetermined temperature to the terminal side, and a control unit that controls the opening degree of the first mixing valve and the use-side mixing valve, and performs a full-boiling operation A hot water storage type hot water supply device that sets a time zone and performs a hot water boiling operation when it is determined that the amount of hot water is insufficient, and the control unit performs the first mixing when a power failure occurs and then returns. Prohibit valve control It is characterized in that the.

  Then, as a hot water usage mode at the time of power failure recovery after the hot water usage in the hot water storage tank has been stagnated for a long time due to a power failure, the control of the first mixing valve is prohibited so as not to supply hot water from the intermediate temperature hot water pipe. Therefore, even if hot water in the hot water tank stagnates during the power outage and the temperature drops at the lower part of the hot water tank and miscellaneous bacteria such as Legionella propagate, the hot water in the upper part of the hot water tank should be used. It is possible to supply hot water without being affected by bacteria.

  The second aspect of the invention is characterized in that the control unit sets the first mixing valve in the hot water side full open state when the power failure is restored, and prohibits the hot water supply from the intermediate temperature hot water pipe.

  And when a power failure occurs and then returns, the first mixing valve is fully open so that hot water is supplied only from the hot water outlet pipe at the top of the tank. The supply can be suppressed. In other words, the hot water supply from the intermediate hot water pipe near the lower part of the hot water storage tank, where the temperature distribution is easy for breeding of bacteria, is prohibited. A predetermined amount of hot and cold water can be ensured by using a relatively high temperature hot water that is difficult for the bacteria to propagate and adjusting to a desired hot water temperature using a use-side mixing valve.

  According to a third aspect of the present invention, the control unit cancels the control prohibition of the first mixing valve when it is confirmed that the full-boiling operation has been completed after the power failure is restored.

  When the total amount of the hot water tank is boiled in the midnight time zone after the power failure is restored and the hot water temperature at the lower part of the hot water tank reaches a temperature at which various germs are killed, for example, 65 ° C., the normal hot water mixing control is performed. Therefore, the germs that proliferated during the power outage are killed, and then effective hot water supply can be performed by hot water mixing control that preferentially uses medium-temperature water in a safe state.

  According to a fourth aspect of the present invention, when the timing of the power failure recovery is a time zone in which the hot water boiling operation is performed, the control unit is in a time zone in which the hot water boiling operation is performed after the first full amount boiling operation time zone has elapsed. After that, the control prohibition of the first mixing valve is canceled.

  And, if the power failure recovery timing is the daytime time period when the hot water boiling operation is performed to boil some of the hot water in the hot water storage tank, the night time period when the first full boiling operation after the power failure is restored is After the daytime has passed, the control prohibition of the first mixing valve is canceled after the daytime has elapsed, and when the power is restored, the control of the first mixing valve is prohibited and hot water is supplied from the medium temperature hot water pipe. To prevent the outflow of various bacteria such as Legionella that propagated in the lower part of the hot water tank during the power outage period. It can be boiled to a temperature of 65 ° C or higher, and after the time period for all the boiling operations has elapsed, hot water mixing control is performed using the control of the first mixing valve, so that various bacteria such as Legionella bacteria can be obtained. not exist It is possible to ensure an effective hot water use mode in state.

  According to a fifth aspect of the present invention, when the timing of the power failure recovery is a time zone in which the full amount boiling operation is performed, the control unit becomes a time zone in which the hot water boiling operation is performed after the next full amount boiling operation time period has elapsed. After that, the control prohibition of the first mixing valve is canceled.

  And if the power failure is restored during the night time when full-boiling operation is performed, it may be impossible to boil up the entire tank in the full-boiling operation at the time of return. The control of the first mixing valve is prohibited until the nighttime period during which the entire amount is heated, and after the entire boiling operation is completed in the next nighttime period, hot water mixing is performed using the control of the first mixing valve. By performing the control, an effective hot water usage form is ensured in the absence of bacteria such as Legionella.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. Note that the present invention is not limited to the embodiments.

(Embodiment 1)
FIG. 1 is a configuration diagram of a hot water storage type hot water supply apparatus according to a first embodiment of the present invention.

  The hot water storage tank 101 is provided with a boiling pipe 102 in which a lower part and an upper part are communicated with each other, and a boiling pump 103 and a heat exchanger 104 are provided in the middle thereof. The water in the lower part of the hot water storage tank 101 is guided to the heat exchanger 104 by the boiling pump 103 through this boiling path, and heated in the process of passing through the heat exchanger 104 to become hot water, and is guided to the upper part of the hot water storage tank 101. The hot water supplied to the hot water storage tank 101 is accumulated in layers in the hot water storage tank 101 in such a manner that the hot water is separated into the upper part and the water is separated into the lower part due to the difference in specific gravity. When the hot water in the hot water storage tank 101 is used, water is supplied from the water supply pipe 105 into the hot water storage tank 101, and the hot water reduced in accordance with the use state is placed in the hot water storage tank 101 at the upper part. The water supplied from 105 is stored in a separated state at the bottom.

The heat pump circuit 106 serving as a heat source for the heat exchanger 104 is composed of a compressor 107, an expansion valve 108, and a forced air-cooled evaporator 110 using a fan 109. Carbon dioxide is used as a refrigerant, and a critical pressure is set on the high-pressure side. It is possible to store hot water close to 90 ° C. by operating in a temperature exceeding that, and hot water storing about 65 ° C. considering Legionella bacteria can be performed at a high COP.

  Next, a use side circuit configuration for supplying hot water in the hot water storage tank 101 to the load side will be described. A hot water discharge pipe 111 for taking out high temperature water is provided at the upper part of the hot water storage tank 101, and the hot water discharge pipe 111 and the water supply pipe 105 are provided. An intermediate hot water discharge pipe 112 for taking out the medium-temperature water is provided at a substantially intermediate portion.

  A bath utilization circuit 116 connected to a lower part of the hot water storage tank 101 through a circulation pump 115 is provided from the hot water outlet pipe 111 to a bath heat exchanger 114 for exchanging heat with hot water in the bathtub 113 and performing a reheating operation. On the secondary side of the bath heat exchanger 114, a bath circulation circuit 119 is connected to the bath adapter 117 of the bathtub 113 and the bath pump 118 circulates the bath water. With the above configuration, the hot water supplied from the upper part of the hot water storage tank 101 is heat-exchanged with the bath water flowing through the bath circulation circuit 119 by the bath heat exchanger 114 and the temperature is lowered, and then returned to the hot water storage tank 101 as intermediate hot water. . If this bath chasing operation continues, the amount of high-temperature water in the upper part of the hot water storage tank 101 decreases and the amount of medium-temperature water accumulated below it increases. This increase phenomenon of intermediate temperature water causes various adverse effects, and is largely related to a decrease in the operating efficiency (COP) of the heat pump circuit 106 during the boiling operation. That is, when the medium temperature water is increased in the lower part of the hot water storage tank 101, heat exchange with the refrigerant of the heat pump circuit 106 is performed in a state where the incoming water temperature of the heat exchanger 104 at the time of boiling is high, and the temperature difference between the refrigerant and the hot water decreases. Heating capacity is reduced. In particular, in a heat pump cycle using carbon dioxide as a refrigerant, since the high-pressure side pressure of the heat pump is high, the degree of decrease in the operating efficiency (COP) of the heat pump becomes significant when the incoming water temperature increases.

  Further, the increase in the medium-temperature water means that the high-temperature water in the upper part of the hot water storage tank 101 is reduced, and the hot water storage capacity is lowered as a whole, leading to a shortage of hot water.

  Therefore, in the present embodiment, as a countermeasure against the warm water, an intermediate hot water pipe 112 is provided at a substantially intermediate portion of the hot water storage tank 101, and hot water supplied from the intermediate hot water pipe 112 and the upper hot water pipe 111 is mixed to obtain a predetermined mixed water. The first mixing valve 120 is provided to obtain the desired temperature, and the valve opening is adjusted by feeding back the hot water temperature detected by the first temperature detector 121 to ensure a predetermined target temperature. By providing the first mixing valve 120, it is possible to preferentially take out the hot water according to the purpose of use, and the hot water in the hot water storage tank 101 can be reduced.

  On the output side of the first mixing valve 120, a load-side circuit corresponding to the application is configured. First, as hot water use, the mixed water from the first mixing valve 120 and the water from the water supply pipe 105 are mixed to set the set temperature. A hot water supply mixing valve 122 which is one of the load side mixing valves for obtaining hot water is provided and supplied to the currant 124. A hot water temperature detector 123 is attached to the output side of the hot water mixing valve 122, and the valve opening is adjusted by feeding back the hot water temperature detected by the hot water temperature detector 123 so as to ensure a set temperature. Yes.

  For bath use, a bath mixing valve 125 is provided as one of the load side mixing valves for mixing the mixed water from the first mixing valve 120 and the water from the water supply pipe 105 to obtain hot water at a set temperature. The bath 113 is connected to the bath circulation circuit 119 via the pouring valve 126 to fill the bathtub 113 with hot water. A bath temperature detector 127 is attached to the output side of the bath mixing valve 125. By adjusting the valve opening by feeding back the hot water temperature detected by the bath temperature detector 127, the set temperature is secured. Yes.

  A check valve 128 is provided in the high-temperature water side supply path of the first mixing valve 120 so as to prevent the backflow of the medium-temperature water from the intermediate tapping pipe 112. In addition, check valves 129 and 130 are provided in the hot water supply path of the hot water supply mixing valve 122 and the bath mixing valve 125, and a check valve 131 is provided on the output side of the hot water supply mixing valve 122.

  A hot water remote controller 132 is provided in the vicinity of the currant 124, and a bath remote controller 133 is provided in the bathroom. The operation instruction from the hot water remote controller 132 or the bath remote controller 133 is sent wirelessly or by wire to a control unit 134 provided on the apparatus body side, and various operations are performed based on the control operations previously defined by the control unit 134 according to the transmitted conditions. I try to do it.

  In addition, the control unit 134 is provided with a power failure detection unit 139 that detects whether or not power is normally supplied from the power line 138, and a timer unit 140 with a calendar function that measures 24 hours. 140 sets the night time zone in which the whole amount heating operation is performed by 140, that is, the midnight power time zone (for example, from 23:00 to 7:00) and the daytime time zone (7 to 23:00) in which the hot water boiling operation is performed, Based on the signal from the power failure detection unit 139, the time zone when the power failure occurs or the time zone when the power failure is restored is determined, and the signal is supplied to the control unit 134.

  The hot water storage type hot water supply apparatus in the present embodiment is configured to boil the entire amount of the hot water storage tank 101 in accordance with a heating mode preset in a midnight power time zone (for example, from 23:00 to 7:00) by a boiling circuit 102 as shown in FIG. The amount of remaining hot water decreases and the amount of hot water decreases based on the temperature detected by the remaining hot water temperature detectors 135, 136, and 137 attached to the wall surface of the hot water storage tank 101 during the daytime period (7 to 23:00). When it seems that the shortage will occur, the hot water boiling operation is performed to secure the necessary amount of hot water in the upper part of the hot water storage tank 101. By the above boiling operation, the hot water storage tank 101 accumulates in layers in the order of high temperature water, medium temperature water, and low temperature water from the top.

  The stored hot water is supplied from the hot water remote controller 132 or the bath remote controller 133 so that the control unit 134 controls the load side mixing valve of the usage side circuit to supply desired hot water to the usage side terminal. Yes.

  An example of the operation of the user side circuit in the present embodiment will be described with reference to FIGS. 3 and 4. First, when a desired hot water supply temperature is set by the hot water supply remote controller 132 and the currant 124 is opened, the water supply pipe 105 is opened. The hot water storage tank 101 is started to supply water, and the hot water and intermediate hot water in the hot water storage tank 101 are discharged from the hot water discharge pipe 111 and the intermediate hot water discharge pipe 112 by the supply water pressure, and the hot water side a and the water side b of the first mixing valve 120 are discharged. To be supplied. At this time, if the water side b is kept fully open as an initial setting of the first mixing valve 120, the medium temperature water in the hot water storage tank 101 is discharged preferentially and supplied to the next stage from the mixing outlet side c. When this hot water temperature is detected by the first temperature detector 121 and the detected hot water temperature is higher than a temperature set by the hot water supply remote controller 132 by a predetermined temperature (for example, 2 ° C.), the valve opening is further increased to the water side. Since it cannot be adjusted, the supply of the medium-temperature water is continued in this state, and the hot water at the set temperature is supplied to the currant 124 by being mixed with the water supplied from the water supply pipe 105 by the hot water supply mixing valve 122 in the next stage.

Next, when the hot water temperature detected by the first temperature detector 121 is lower than the temperature set by the hot water remote controller 132, the opening of the hot water side a of the first mixing valve 120 is opened and the high temperature from the high temperature hot water discharge pipe 111 is opened. Control of the valve opening is started so that water is taken in and mixed with warm water to reach the target temperature (hot water flows through the path indicated by the thick line). By this control, the outlet temperature of the first mixing valve 120 gradually approaches the target temperature, and hot water having a preset target temperature is supplied to the hot water side d of the hot water supply mixing valve 122 in the next stage. Then, the hot water at the set temperature is mixed with the water supplied from the water supply pipe 105 by the hot water supply mixing valve 122 so that the hot water at the set temperature is obtained.
To supply.

  As described above, in the normal operation, the hot water is supplied to the use side terminal such as the currant 124 by preferentially using the medium temperature water accumulated in the hot water storage tank 101 by the first mixing valve 120. The low-temperature water can be secured, the use of the high-temperature water above the hot water tank can be minimized, the boiling operation of the high COP and the suppression of the hot water phenomenon can be achieved. A very effective means can be secured as a hot water utilization form.

  However, when the power supply is stopped due to a power failure or the like, the preferential usage mode of the medium-temperature water in the above configuration is that the heating operation is stopped and the load-side mixing valve is subjected to the water-side fully open stop process. If the hot water in the hot water storage tank 101 cannot be used and the power outage period continues for a long time, the hot water temperature in the hot water storage tank 101 decreases, and the temperature distribution becomes easier for germs to propagate in the lower part of the hot water storage tank 101. If Legionella is propagated, it may harm the human body. In other words, during the power outage period, when bacteria such as Legionella have propagated and the power recovers from the power outage, the hot water is preferentially taken out from the intermediate hot water outlet 112 near the bottom of the hot water storage tank where the various bacteria have propagated. It will be discharged from the pipe 112 at an early stage of hot water use after the power failure is restored, and discharged to the outside through the currant 124 or the like. If Legionella bacteria are mixed in the discharged germs, they will be scattered in the air, which will adversely affect the human body from the respiratory system.

  Therefore, the hot water supply apparatus in the present embodiment sends a signal to the control unit 134 when the power failure is detected by the power failure detection unit 139 and then the recovery of the power failure is detected, and the hot water side a of the first mixing valve 120 And then the control of the first mixing valve 120 is prohibited until a control prohibition release signal is output from the control unit 134 when a predetermined condition is satisfied and a control prohibition release signal is output. The side is fully open.

  By this control, the hot water usage form after the power failure is restored is that hot water supplied from the upper outlet pipe 111 of the hot water storage tank 101 is transferred to the hot water side d of the hot water supply mixing valve 122 which is a load side mixing valve via the first mixing valve 120. The hot water at the set temperature is used from the currant 124 by being supplied and mixed with the water supply e supplied from the water supply pipe 105.

  Even if miscellaneous bacteria such as Legionella bacteria propagate in the lower part of the hot water storage tank 101 during this blackout period, hot water supply from the intermediate temperature hot water discharge pipe 112 is prohibited in the hot water supply use after the power failure is restored. Since the upper hot water in the upper part is preferentially used, the outflow of various bacteria can be suppressed.

  When the entire amount of the hot water storage tank 101 is heated after the power failure is restored, and the total amount in the hot water storage tank 101 reaches a temperature at which miscellaneous bacteria such as Legionella bacteria are killed, for example, 65 ° C. or more, the controller 134 controls the first mixing valve. The control prohibition release signal 120 is output, and the mixing control by normal temperature hot water preferential extraction from the medium temperature hot water discharge pipe 112 is resumed.

As a specific embodiment, when the power failure recovery timing is a daytime period in which a hot water boiling operation is performed to raise a part of the hot water in the hot water storage tank 101, the first full boiling operation after the power failure is restored The control prohibition of the first mixing valve 120 is canceled after the daytime time period after the midnight power time period has elapsed, and the control of the first mixing valve 120 is prohibited when the power failure is restored. In order to prohibit the supply of hot water from the intermediate temperature hot water discharge pipe 112, it is possible to prevent the outflow of various bacteria such as Legionella bacteria that have propagated in the lower part of the hot water storage tank 101 during the power outage period, and the hot water storage can be performed after the midnight power hours The entire tank, including the hot water at the bottom of the tank 101, can be heated to a hot water temperature of 65 ° C. or higher at which Legionella bacteria are killed. By performing the hot and cold water mixing control, it is possible to ensure effective hot water utilization form in the absence of bacteria, such as Legionella using.

  In addition, if a power failure is restored during the midnight power hours during which the entire amount is heated up, it may be impossible to boil up the entire amount of the tank during the full amount boiling operation. The control of the first mixing valve 120 is prohibited until the midnight power time period during which the full amount boiling operation is performed, and after the full boiling operation is completed in the next midnight power time zone, the control of the first mixing valve 120 is performed. By using hot water and water mixing control, an effective hot water usage form is ensured in the absence of bacteria such as Legionella.

  The specific control operation in the above embodiment will be described with reference to the flowcharts of FIGS. 5 and 6. First, in FIG. 5, the normal operation by preferential use of the medium temperature water from the medium temperature hot water discharge pipe 112 is performed in step 1. If it is determined in step 2 that the power failure detection unit 139 normally supplies power from the power line 138, and if it is determined that power is not supplied due to a power failure or the like, step 3 In the state where the heating operation and the mixing valve control are stopped, the power supply is restored. When it is determined in step 4 that the power failure has been restored by the power failure detection unit 139 and the power supply has been restored, a signal is sent to the control unit 134 to set the valve opening of the first mixing valve 120 to the fully open state on the hot water side a. After that, the control of the valve opening degree of the first mixing valve 120 is prohibited. Next, in step 6, it is determined whether or not the entire boiling water heating operation of the hot water storage tank 101 has been completed, and when it is determined that it has been completed, that is, when the hot water temperature in the hot water storage tank 101 has become a predetermined temperature or higher, step 8, the control prohibition state of the first mixing valve 120 is canceled and the normal operation is restored.

  Next, a more detailed control operation in FIG. 6 will be described. Steps 11 to 14 are the same as those in FIG. When the power failure recovery is determined in step 14, it is determined in step 15 which time zone the power failure recovery timing is. If there is a power failure recovery in the daytime time period, the valve of the first mixing valve 120 is determined in step 16. The opening is driven so that the hot water side a is fully opened, and then the control of the opening of the first mixing valve 120 is prohibited. Next, it is determined in step 17 whether or not the night time zone has been reached. In the case of the night time zone, the boiling-up operation of the entire amount is started in step 18, and the night time zone is ended and the day time zone is reached in step 19 If it is determined that it is during the daytime period, it is determined that all the boiling has been completed, and in step 20, the control prohibition state of the first mixing valve 120 is canceled and the normal operation is restored. ing.

  When it is determined in step 15 that the power failure has been restored during the nighttime period, the valve opening of the first mixing valve 120 is driven in step 21 so that the hot water side a is fully opened, and then the first mixing valve 120 is driven. The control of the valve opening of the valve is prohibited. Next, in step 22, the full-boiling operation is started, and in step 23, it is determined whether or not the night time zone in which the full-boiling operation is performed has been completed. In this case, since it is assumed that the full-boiling operation is stopped in a state where the full-boiling condition is not satisfied depending on the timing of the power failure recovery in the night time zone, the control of the first mixing valve 120 in the first daytime zone is assumed. When the prohibition state is canceled, the next night time zone is determined in step 24, the full boiling operation is started in step 25, and the daytime zone is confirmed in step 26. In step 27, the first mixing valve 120 is started. The control prohibit state is canceled and the normal operation is restored.

  As described above, the hot water storage type hot water supply apparatus of the present invention provides a hot water mixing control method capable of preferentially using medium hot water, which is an extremely effective means as a hot water use form of the heat pump hot water supply apparatus, while hot water is supplied by a power failure or the like. This ensures safety when the use of stagnation is stagnant, and can be applied to hot and cold water mixing control in general regardless of the heat source.

The block diagram of the hot water storage type hot water supply apparatus in Embodiment 1 of this invention The figure which shows the boiling operation in the hot water storage type hot water supply apparatus The figure which shows an example of the hot water usage form in the hot water storage type hot water supply apparatus The figure which shows another example of the hot water usage form in the hot water storage type hot water supply apparatus Flow chart showing control operation in the hot water storage type hot water supply apparatus The flowchart which shows another control action in the hot water storage type hot water supply apparatus

Explanation of symbols

DESCRIPTION OF SYMBOLS 101 Hot water storage tank 105 Water supply pipe 106 Heat pump circuit 111 Hot water discharge pipe 112 Medium temperature hot water supply pipe 120 1st mixing valve 122 Hot water supply mixing valve (load side mixing valve)
125 Bath mixing valve (load-side mixing valve)
134 Control unit 139 Power failure detection unit 140 Timer unit

Claims (5)

In a hot water storage hot water supply apparatus that stores hot water heated using a heat pump circuit in a stratified state from the upper part of the tank and supplies the desired hot water to the terminal side using the hot water,
A tapping pipe for taking out hot water at the upper part of the tank, a medium temperature tapping pipe for taking out hot water at a substantially middle part of the tank, a first mixing valve for mixing hot water from the tapping pipe and the middle temperature tapping pipe, and the first mixing valve. A use-side mixing valve that mixes hot water and water from a water supply pipe and supplies hot water at a predetermined temperature to the terminal side, and a controller that controls the opening degree of the first mixing valve and the use-side mixing valve,
A hot water storage type hot water supply apparatus that sets a time zone for performing a full-boiling operation and sets a hot-water boiling operation when it is determined that the amount of hot water is insufficient,
The said control part is a hot water storage type hot-water supply apparatus which prohibited control of a said 1st mixing valve, when a power failure generate | occur | produces and it returns after that. The hot water storage hot water supply apparatus according to claim 1, wherein the control unit sets the first mixing valve to the hot water side full open state when the power failure is restored, and prohibits the hot water supply from the intermediate temperature hot water pipe. The hot water storage type hot water supply apparatus according to claim 1 or 2, wherein the control unit cancels the control prohibition of the first mixing valve when it is confirmed that the whole amount boiling operation has been completed after the recovery from the power failure. In the case where the power failure recovery timing is a time zone in which the hot water boiling operation is performed, the control unit is in a time zone in which the hot water boiling operation is performed after the first full amount boiling operation time zone has elapsed. The hot water storage type hot water supply apparatus according to claim 1 or 2, wherein the prohibition of control of one mixing valve is canceled. When the timing for recovering from the power failure is a time zone in which the whole amount boiling operation is performed, the control unit first enters the time zone in which the hot water boiling operation is performed after the next full amount boiling operation time zone has elapsed. The hot water storage type hot water supply apparatus according to claim 1 or 2, wherein the prohibition of control of the mixing valve is canceled.