JP4635787B2 - Hot water storage water heater - Google Patents

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 a very effective means as a hot water usage form of the device, on the other hand, when leaving the house for a short time due to travel etc., the power supply is shut off and the heating operation during that period is stopped. In consideration of such a situation, a switch is provided in the remote control device that can set the pause period of the boiling operation without shutting off the power supply. There is something that can stop normal boiling operation for the number of days away from home, and when this heating operation is stopped, the use of hot water in the hot water tank is stagnated for a long time, and the hot water storage tank The temperature of the hot water inside falls. If it does so, miscellaneous bacteria may grow, and if Legionella bacteria propagate, there is a risk of harming the human body. This Legionella bacterium is actively active in the 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 during the period of the boiling operation. 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 and cold water mixing control method capable of preferentially using medium hot water, which is an extremely effective means for using hot water in a heat pump hot water supply apparatus, while stopping boiling. 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 a state.

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. And a control unit for performing a full-boiling operation, setting a time for performing a hot-water boiling operation when it is determined that the amount of hot water is insufficient, and arbitrarily setting a predetermined number of days. Boil up for a set number of days A hot water storage type hot water supply apparatus capable of setting to make a pause, the control unit, when the boiling pause period is set, the first mixing valve, and fully open state to the hot water pipe side It is made to drive so that it may become .

  According to the above invention, when it is assumed that the use of hot water in the hot water storage tank is stagnated for a long time due to the setting of the boiling suspension period, the first mixing valve is not supplied from the hot hot water pipe. Because the control is prohibited, even if the hot water in the hot water tank stagnates during the boiling pause period, and the temperature drops at the bottom of the hot water tank and miscellaneous bacteria such as Legionella propagates, the boiling pause period ends. Later, or in the hot water usage mode during the boiling stop period, the hot water can be used from a relatively hot water in the upper part of the hot water storage tank, and 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 temperature water as an extremely effective means for using hot water in a heat pump type hot water supply apparatus, while setting hot water in a boiling pause period. It is possible to provide a hot water storage type hot water supply device that ensures safety when the use of the water is stagnant.

A first 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 a 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 intermediate portion 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 Set the time zone, set to run out of hot water when it is judged that the amount of hot water is insufficient, and pause the boiling operation for an arbitrarily set number of days within a predetermined number of days. Hot water storage that can be set A water heater, the control unit, when the boiling pause period is set, the first mixing valve, is characterized in that the driving so that the fully open state to the hot water pipe side .

  And when it is assumed that the use of hot water in the hot water storage tank is stagnated for a long time due to the setting of the boiling suspension period, 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 the hot water in the hot water storage tank stagnates during the boiling suspension period and a temperature drop occurs in the lower part of the hot water storage tank and other bacteria such as Legionella bacteria propagate, In the form of hot water during the lifting suspension period, the hot water can be used from the relatively hot water at the upper part of the hot water storage tank, and hot water can be supplied without being affected by various bacteria.

In addition, the control unit is characterized in that when the boiling pause period is set, the first mixing valve is fully opened to prohibit the hot water supply from the medium temperature hot water pipe.

And when the boiling stop period is set, since the first mixing valve is in the hot water side full open state so as to supply hot water only from the tapping pipe , after the boiling stop period ends or during the boiling stop period In the utilization form of hot water, it is possible to suppress the supply of miscellaneous bacteria propagated in the lower part of the hot water storage tank to the use side terminal. 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.

The second aspect of the invention is characterized in that the control unit returns the hot water / water mixing control of the first mixing valve when the completion of the whole amount boiling operation is confirmed after the boiling suspension period ends. .

  Then, when the whole amount of the hot water tank is boiled in the midnight time period after the end of the boiling stop period and the hot water temperature at the lower part of the hot water tank reaches a temperature at which miscellaneous bacteria die, for example, 65 ° C., normal hot water mixing control is performed. Since it has been restored, the germs that proliferated during the power outage are killed, and after that, 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 third aspect of the present invention, the control unit performs a full-boiling operation from the night time zone on the day when the boiling suspension period ends, and restores the hot water / water mixing control of the first mixing valve after the day time zone. It is a feature.

  Then, the operation restart after the boiling stop is performed from the next day after the set stop period ends, but the entire amount is heated from the night time zone on the end of the stop period. Efficient hot water supply by hot water mixing control that preferentially uses medium-temperature water in a safe state by canceling the control prohibition of the first mixing valve by judging that the total amount is above the temperature at which germs are killed Like to do.

The fourth aspect of the invention is characterized in that when the boiling stop setting is forcibly released, the control unit does not return the hot water / water mixing control of the first mixing valve until it is confirmed that the full boiling operation has been completed. To do.

  And, for example, when the operation is forcibly restarted by the operation for canceling the pause setting, the test operation, or the manual boiling operation during the boiling suspension period, the completion of the total boiling operation is confirmed until Prohibit the control of 1 mixing valve, complete the boiling operation, that is, when the night time zone has passed and the daytime time zone has passed, cancel the control prohibition of the 1st mixing valve and breed during the pause period Effective hot water supply can be performed by hot and cold water mixing control that preferentially uses medium-temperature water without being affected by various germs.

  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 this 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 111 is mixed to obtain a predetermined mixed water. A first mixing valve 120 for obtaining the temperature is provided and the valve opening degree 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.

  Note that a check valve 128 is provided in the intermediate temperature water supply path of the first mixing valve 120 so as to prevent backflow into 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.

  The hot water supply remote controller 132 or the bath remote controller 133 has a heating operation stop setting operation unit 138, 139 that can put the heating operation in a pause state when the house is temporarily absent during travel or the like, The boiling operation can be suspended for the number of days arbitrarily set by the heating operation suspension setting operation units 138 and 139 for a predetermined number of days. For example, the predetermined number of days is about 14 days (2 weeks), and if it is longer than that, it is desirable to shut off the power and drain the hot water in the tank. Then, when an arbitrary pause period is set by the boiling operation pause setting operation unit 138, 139, the information is sent to the control unit 134, and the control unit 134 stops all the boiling operations performed in the normal operation. Thus, when the outside air temperature is lowered and the possibility of freezing occurs, the boiling operation is performed by a predetermined freeze prevention sequence.

  In addition, the control unit 134 is provided with a timer unit 140 with a calendar function that measures 24 hours, and the timer unit 140 performs a full-time boiling operation, that is, a midnight power period (for example, 23:00) ~ 7 o'clock) and a daytime time zone (7 o'clock to 23 o'clock) during which the hot water boiling operation is performed, and the pause period set by the boiling operation pause setting operation unit 138, 139 is counted and paused. At the end of the period, 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 supply 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 supply remote controller 132, the opening of the hot water side a of the first mixing valve 120 is opened and hot water from the hot water outlet pipe 111 is opened. Then, the valve opening is controlled so as to reach the target temperature by mixing with hot water (hot water flows along 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 mixing valve 122 mixes with the water supply from the water supply pipe 105 and supplies hot water having a set temperature to the currant 124.

  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 heating operation stop period is set by the boiling operation stop setting operation unit 138, 139, the hot water flow in the hot water storage tank 101 stagnates and the preferential usage form of the medium temperature water in the above configuration is The hot water temperature in the hot water storage tank 101 decreases with the passage of time, and the temperature distribution is such that miscellaneous bacteria are likely to propagate in the lower part of the hot water storage tank 101. In particular, if Legionella bacteria are propagated, the human body may be harmed. In other words, the state in which the pause period ends and the hot water supply operation is restarted while miscellaneous bacteria such as Legionella bacteria have propagated during the boiling operation pause period, or the hot water supply operation is forcibly restarted during the pause period. Then, since hot water is preferentially taken out from the intermediate temperature hot water pipe 112 near the lower part of the hot water storage tank where the various germs have propagated, the propagated germs will be discharged from the intermediate temperature hot water pipe 112 at an early stage of hot water use after resuming the hot water supply operation. , 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 boiling operation suspension period is set by the boiling operation suspension setting operation units 138, 139, and the hot water of the first mixing valve 120 is transmitted. The valve opening on the side a is driven so as to be fully open, and then the control of the first mixing valve 120 is prohibited until a predetermined condition is satisfied and a control prohibition release signal is output from the controller 134. The hot water side is fully opened.

  By this control, the hot water usage form after the boiling operation suspension period ends or during the suspension period is a load-side mixing valve for supplying hot water supplied from the upper hot water discharge pipe 111 of the hot water storage tank 101 via the first mixing valve 120. The hot water at the set temperature is used from the currant 124 by being supplied to the hot water side d of the hot water supply mixing valve 122 and mixed with tap water on the water side e supplied from the water supply pipe 105.

  Even if miscellaneous germs such as Legionella bacteria propagate in the lower part of the hot water storage tank 101 during the boiling operation suspension period, the use of the hot water hot water pipe 112 after the boiling operation suspension period or in hot water use during the suspension period is possible. Therefore, the hot water supply at the upper part of the tank is preferentially used, so that the outflow of germs can be suppressed.

  Then, after the boiling operation suspension period ends, the hot water storage tank 101 is fully heated, and when the total amount in the hot water storage tank 101 reaches a temperature at which miscellaneous bacteria such as Legionella bacteria die, for example, 65 ° C. or more, the control unit 134 A control prohibition release signal for the first mixing valve 120 is output to resume normal mixing control by taking out the medium temperature water from the medium temperature hot water discharge pipe 112.

  As a specific embodiment thereof, an arbitrary boiling operation suspension period is set by the boiling operation suspension setting operation unit 138, 139, and the entire amount boiling operation is performed from the night time zone on the day when the suspension period ends. The control prohibition of the first mixing valve 120 is canceled after the daytime period after the time period has elapsed, and the control of the first mixing valve 120 is prohibited during the pause period, so that the intermediate temperature hot water pipe Since the supply of hot water from 112 is prohibited, 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 boiling operation suspension period. The entire tank containing hot water at the bottom can be boiled to a temperature of 65 ° C. or higher at which Legionella bacteria are killed. By performing the hot and cold water mixing control using the control, it is possible to ensure an effective hot water utilization form in the absence of bacteria, such as Legionella. In this way, by carrying out the full-boiling operation from the night time zone on the end date of the pause period, effective hot and cold water mixing control using medium-temperature water can be performed from the next morning after the set pause period ends.

  In addition, when the schedule is changed during the boiling operation suspension period and when the suspension setting is canceled when returning home, the control of the first mixing valve is prohibited until the completion of the full boiling operation is confirmed. Thereafter, the control prohibition of the first mixing valve is canceled after the daytime time zone after the nighttime time zone has passed and the whole amount heating operation has been performed. Thereby, the effective hot water utilization form is securable in the state in which miscellaneous bacteria, such as Legionella bacteria, do not exist.

  A specific control operation in the above embodiment will be described with reference to the flowchart of FIG. 5. First, in FIG. 5, a normal operation is performed by preferential use of the intermediate temperature water from the intermediate temperature hot water pipe 112 in Step 1. In step 2, it is determined whether or not the boiling operation stop period is set by the boiling operation stop setting operation units 138 and 139. If it is determined that the stop period is set, the boiling operation is stopped in step 3. In step 4, the valve opening of the first mixing valve 120 is driven so that the hot water side a is fully opened, and then the control of the valve opening of the first mixing valve 120 is prohibited. Next, it is determined in step 5 whether or not the suspension period has ended. If it is determined that the suspension period has not ended, it is determined in step 6 whether or not the suspension period has been set. If it is determined in step 5 that the suspension period has ended and if it is determined in step 6 that the suspension period has been set, the full-boiling operation is started in step 7, and the full-boiling operation is performed in step 8. When it is confirmed that the operation has been completed, the control prohibition state of the first mixing valve 120 is canceled in step 9 to return to the normal operation.

  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 temperature water, which is an extremely effective means as a hot water use form of the heat pump type hot water supply apparatus, It ensures safety when hot water usage stagnate due to the setting of the suspension period, and can be applied to hot 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

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 138, 139 Boiling operation stop setting operation unit 140 Timer unit

Claims (4)

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,
Set the time period for performing all-boiling operation, set to perform boiling-out boiling operation when it is judged that the hot water amount is insufficient, and perform boiling operation for an arbitrarily set number of days within a predetermined number of days A hot water storage type hot water supply device that can be set to perform a pause of
The controller is configured to drive the first mixing valve so that the first mixing valve is fully opened toward the hot water pipe when the boiling stop period is set. The hot water storage type hot water supply apparatus according to claim 1, wherein the control unit returns the hot water / water mixing control of the first mixing valve when it is confirmed that the whole amount boiling operation has been completed after the boiling suspension period ends. Control unit performs a heating operation the total amount from the nighttime day rest period boiling is completed, after becoming daytime, in claim 2 which is adapted to return the hot and cold water mixing control of the first mixing valve The hot water storage type hot water supply apparatus described. 2. The hot water storage device according to claim 1, wherein when the boiling stop setting is forcibly cancelled, the control unit does not return the hot water / water mixing control of the first mixing valve until the completion of the full boiling operation is confirmed. Water heater.