Hot water storage unit

Abstract

To provide a hot water storage water heater which is stored in a storage part with ventilation door of a building, and which suppresses corrosion of devices in the storage part and a ventilation door due to combustion exhaust when simultaneously operating a heat pump heat source machine and a combustion type auxiliary heat source machine.SOLUTION: A hot water storage water heater (1) includes a control part (5) for controlling a hot water storage operation for heating hot water and storing it in a hot water storage tank. The hot water storage water heater (1) installed in a storage part (S) with ventilation door of a building comprises a heat pump heat source machine (3) for heating hot water in a hot water storage operation, a combustion type auxiliary heat source machine (4) and a hot water storage tank (2). In the case where the heat pump heat source machine (3) and the auxiliary heat source machine (4) are operated simultaneously, when a combustion load of the auxiliary heat source machine (4) is equal to or greater than a first threshold value, the operation of the heat pump heat source machine (3) is restricted, and when the combustion load becomes equal to or greater than a second threshold value which is larger than the first threshold value, the operation of the heat pump heat source machine (3) is stopped.SELECTED DRAWING: Figure 6

Description

[Technical Field]

[0001] The present invention relates to a hot water storage and hot water supply system that stores hot water heated by a heat pump heat source in a hot water storage tank and uses it for hot water supply, and more particularly to a hot water storage and hot water supply system in which a hot water storage tank, a heat pump heat source, and an auxiliary heat source are housed in a building's accommodation section with a ventilation door. [Background technology]

[0002] Conventionally, hot water storage and hot water supply systems that store hot water heated by a heat pump heat source in a hot water storage tank for use in hot water supply, and when the stored hot water cannot be used for hot water supply, heat it using an auxiliary heat source to supply hot water have been widely used in detached houses, etc. The hot water storage and hot water supply unit is configured by housing the hot water storage tank, auxiliary heat source, hot water supply piping, etc. in an exterior case, and the heat pump heat source unit, which heats the hot water using heat from outside air, is configured separately from the hot water storage unit to allow easy passage of outside air.

[0003] When such a hot water storage and hot water supply device is used in, for example, an apartment building, no outer case is used, and the hot water storage tank, heat pump heat source unit, and auxiliary heat source unit are installed in a storage area with a ventilation door (an installation space generally called a pipe space or meter box) built into the building. For example, Patent Document 1 describes a heat pump water heater in which a hot water storage tank and a heat pump heat source are housed in a housing section with a ventilation door. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Japanese Patent Application Laid-Open No. 2011-127796 Summary of the Invention [Problem to be solved by the invention]

[0005] In a hot water supply system with a heat pump, a hot water tank, and a combustion-type auxiliary heat source, the heat pump is controlled to operate first to store hot water in the hot water tank, but if the hot water tank runs out of hot water, the heat pump and auxiliary heat source operate simultaneously. During this simultaneous operation, the heat pump draws outside air into the housing, along with combustion exhaust gas from the auxiliary heat exchanger, which can corrode the equipment and ventilation doors inside the housing due to corrosive substances contained in the combustion exhaust gas.

[0006] The object of the present invention is to provide a hot water storage and hot water supply device that is housed in a storage section with a ventilation door of a building, and that is designed to suppress corrosion of the equipment and ventilation door inside the storage section due to combustion exhaust when a heat pump heat source unit and a combustion-type auxiliary heat source unit are operated simultaneously. [Means for solving the problem]

[0007] The hot water storage and water heating device of claim 1 is a hot water storage and water heating device equipped with a control unit that controls hot water storage operation in which hot water is heated and stored in a hot water storage tank, and in which a heat pump heat source unit that heats hot water in hot water storage operation, a combustion-type auxiliary heat source unit, and a hot water storage tank are installed in a storage section with a ventilation door of a building, and is characterized in that when the heat pump heat source unit and the auxiliary heat source unit are operating simultaneously, the operation of the heat pump heat source unit is limited when the combustion load of the auxiliary heat source unit is above a first threshold.

[0008] According to the above configuration, when the heat pump heat source unit and the auxiliary heat source unit are operating simultaneously, the fan of the evaporative heat exchanger of the heat pump heat source unit operates, causing the combustion exhaust gas from the auxiliary heat source unit to be drawn into the storage unit. This combustion exhaust gas can easily corrode the equipment, ventilation doors, etc. in the storage unit, but because operation of the heat pump heat source unit is limited when the combustion load of the auxiliary heat source unit is equal to or greater than the first threshold, corrosion of the equipment, ventilation doors, etc. in the storage unit can be suppressed.

[0009] The hot water storage and heating device of claim 2 is characterized in that, in the invention of claim 1, operation of the heat pump heat source unit is stopped when the combustion load of the auxiliary heat source unit becomes equal to or greater than a second threshold value that is greater than the first threshold value. According to the above configuration, when the combustion load of the auxiliary heat source unit becomes equal to or greater than a second threshold value that is greater than the first threshold value, the operation of the heat pump heat source unit is stopped, thereby preventing corrosion of equipment, ventilation doors, etc. inside the storage unit due to combustion exhaust gases.

[0010] The hot water storage and heating device of claim 3 is characterized in that, in the invention described in claim 1 or 2, the operation of the heat pump heat source unit is not restricted when the heat pump heat source unit is performing anti-freeze operation or defrost operation. According to the above configuration, the operation of the heat pump heat source unit is not restricted when the heat pump heat source unit is performing anti-freeze operation or defrost operation, so that the anti-freeze operation and defrost operation can be performed reliably.

[0011] The hot water storage and boiler device of claim 4 is characterized in that, in the invention of claim 2, the first threshold value is a combustion load of 30%, and the second threshold value is a combustion load of 60%. According to the above configuration, the first threshold is a combustion load of 30% and the second threshold is a combustion load of 60%, so that when the combustion load is between 30% and 60%, the operation of the heat pump heat source unit is limited according to the combustion load, and when the combustion load is 60% or higher, the operation of the heat pump heat source unit is stopped. [Effects of the Invention]

[0012] As described above, the present invention provides various effects. [Brief explanation of the drawings]

[0013] [Figure 1] A front view of a storage section with a ventilation door in which a hot water storage and hot water supply device according to an embodiment of the present invention is stored. [Figure 2] A side view showing an example of how a hot water storage and hot water supply device is accommodated in a storage section with a ventilation door. [Figure 3] FIG. 1 is a diagram illustrating the configuration of a hot water storage and heating device. [Figure 4] FIG. 2 is an explanatory diagram of a heat pump heat source machine. [Figure 5] 10 is a flowchart of heat pump heat source unit output limit control. [Figure 6] FIG. 4 is an explanatory diagram of a map used in the above control. DETAILED DESCRIPTION OF THE INVENTION

[0014] Hereinafter, the mode for carrying out the present invention will be described based on examples. [Example]

[0015] In a multi-story apartment building, a pipe space S for vertically passing pipes such as water pipes and gas pipes for each unit is provided facing, for example, a common passageway. As shown in Figures 1 and 2, this pipe space S is usually equipped with openable and closable doors (here, four doors D1 to D4), and the hot water storage and heating device 1 is housed within this pipe space S. Arrow U indicates the upward direction, arrow R indicates the right direction, and arrow F indicates the forward direction.

[0016] Gaps G that allow air to flow in and out are provided above doors D1 and D2 and below doors D3 and D4. A water meter, a gas meter, etc. may be placed in this pipe space S, which is sometimes called a meter box. Hereinafter, the pipe space or meter box will be referred to as the storage section S.

[0017] The storage compartment S accommodates the hot water supply device 1. The hot water supply device 1 has a hot water storage tank 2, a heat pump heat source unit 3 that heats the hot water in the hot water storage tank 2 by a heating operation and stores the hot water in the hot water storage tank 2, a combustion-type auxiliary heat source unit 4, and a control unit 5 that controls the hot water storage operation for storing hot water in the hot water storage tank 2, etc. The hot water storage tank 2 and the auxiliary heat source unit 4 are installed in the storage compartment S without being housed in an exterior case, and the heat pump heat source unit 3 is also installed in the same storage compartment S. The hot water supply device 1 is used with the doors D1 to D4 closed. The control unit 5 may be housed in the storage compartment S, or may be installed indoors.

[0018] The hot water storage tank 2 is formed in a tall cylindrical shape so that a large amount of hot water can be stored in a small installation area, and is installed, for example, at the back (rear) of the storage section S. The auxiliary heat source unit 4 is disposed at the top of the storage section S so as to face door D2, which has an opening OP2 located at a high position so that the combustion exhaust does not directly hit people in front of the storage section S, and is fixed to a metal frame (not shown). The heat pump heat source unit 3 is installed below the auxiliary heat source unit 4 so as to face doors D3 and D4, making effective use of the limited space within the storage section S. The hot water storage tank 2 is covered with thermal insulation material (not shown), and hot water passages, pumps, and valves (described below) are installed around the hot water storage tank 2.

[0019] The heat pump heat source unit 3 has a blower fan 36 that is driven to take in air from the storage unit S to heat hot water and blow it out of the storage unit S. For this reason, doors D3 and D4 of the storage unit S are ventilation doors with louvers that have openings OP3 and OP4. The auxiliary heat source unit 4 takes in air for combustion from inside the storage unit S to heat hot water and expels the combustion exhaust gas outside the storage unit S. For this reason, an exhaust pipe 6 of the auxiliary heat source unit 4 extends from the opening OP2 of this door D2 to the outside of the storage unit S. Doors D1 to D4 are generally made of metal, which is non-flammable and highly durable.

[0020] Next, the hot water storage and heating apparatus 1 will be described with reference to FIG. The hot water storage and hot water supply device 1 performs hot water storage operation, storing hot water heated to a predetermined hot water storage set temperature in the hot water storage tank 2 by the heating operation of the heat pump heat source unit 3. The combustion-type auxiliary heat source unit 4 supplies hot water at a predetermined hot water supply set temperature to the hot water tap F, with or without performing combustion operation, depending on the temperature of the hot water to be supplied.

[0021] The control unit 5 predicts future hot water usage based on the learned and stored hot water usage record, and controls the hot water storage operation so that the required heat amount corresponding to the predicted hot water usage amount is stored in the hot water storage tank 2 before hot water usage.

[0022] A supply passage 8 equipped with a pump 7 for supplying hot water from the hot water storage tank 2 to the heat pump heat source unit 3 is connected to the bottom of the hot water storage tank 2. A return passage 9 for storing hot water heated by the heating operation of the heat pump heat source unit 3 in the hot water storage tank 2 is connected to the top of the hot water storage tank 2. A switching valve 10 for switching the hot water flow path is provided in the middle of the return passage 9, and a branch passage 9a branched from the return passage 9 by this switching valve 10 is connected to a portion of the supply passage 8 upstream of the pump 7.

[0023] A temperature sensor 9b is disposed in the return passage 9 upstream of the switching valve 10 to detect the temperature of the hot water heated by the heat pump heat source unit 3. For example, if the temperature detected by the temperature sensor 9b immediately after the heat pump heat source unit 3 is started is lower than the predetermined hot water storage set temperature, the switching valve 10 is switched from the hot water storage tank 2 side to the branch passage 9a side, and the hot water is circulated without being returned to the hot water storage tank 2 until it can be heated sufficiently.

[0024] A water supply passage 11, indicated by arrow CW, which supplies clean water is connected to the bottom of the hot water storage tank 2. A hot water outlet passage 12, which discharges hot water from the hot water storage tank 2, is connected to the top of the hot water storage tank 2. A water supply branch passage 11a, which branches off from the water supply passage 11, is connected to a mixing valve 14 disposed in the hot water outlet passage 12. The mixing valve 14 mixes the hot water discharged from the hot water storage tank 2 with clean water and discharges the hot water. Instead of the mixing valve 14, a flow rate adjustment valve that adjusts the flow rate on the hot water storage tank 2 side and a flow rate adjustment valve that adjusts the flow rate on the water supply branch passage 11a side may be used to adjust the mixing ratio of the hot water and clean water.

[0025] A plurality of hot water temperature sensors 2a to 2d that detect the temperature of the hot water are arranged at predetermined intervals in the vertical direction around the outer periphery of the hot water tank 2. The hot water temperature sensors 2a to 2d and the hot water tank 2 are covered with a heat insulating material (not shown) to reduce heat radiation from the stored hot water.

[0026] A water supply temperature sensor 11b is disposed in the water supply passage 11 to detect the temperature of clean water (water supply temperature) supplied from the water supply passage 11. A water outlet passage 12 is disposed in the hot water outlet flow rate sensor 12a to detect the hot water outlet flow rate at the outlet of the hot water outlet passage 12, a tank hot water outlet temperature sensor 12b to detect the temperature of hot water discharged from the hot water storage tank 2 (hot water storage tank outlet temperature), and a hot water outlet temperature sensor 12c to detect the outlet temperature of hot water whose temperature has been adjusted by the mixing valve 14.

[0027] The hot water outlet passage 12 and the water supply port 4a of the auxiliary heat source unit 4 are connected by a hot water passage 15. The hot water supply port 4b of the auxiliary heat source unit 4 is connected to a hot water supply passage 16, and a hot water tap F is connected to the hot water supply passage 16. The auxiliary heat source unit 4 has an inlet water temperature sensor 4c that detects the inlet water temperature of the hot water entering from the water inlet 4a, a hot water supply temperature sensor 4d that detects the hot water supply temperature of the hot water supplied from the hot water supply outlet 4b, and a hot water supply flow rate sensor 4e that detects the hot water supply flow rate. The hot water discharged from the hot water outlet passage 12 is supplied to the hot water tap F via the auxiliary heat source unit 4 and is supplied from the hot water tap F as shown by the arrow HW.

[0028] Based on the tank outlet hot water temperature detected by tank outlet hot water temperature sensor 12b, the feed water temperature detected by feed water temperature sensor 11b, and the hot water outlet flow rate detected by feed water flow rate sensor 12a, control unit 5 adjusts the mixing ratio of tap water and hot water in mixing valve 14 and dispenses hot water so that the temperature detected by outlet hot water temperature sensor 12c becomes a preset hot water supply setting temperature or a predetermined combustion operation start temperature. Control unit 5 also calculates the stored hot water heat quantity based on the temperatures detected by stored hot water temperature sensors 2a to 2d.

[0029] During the heating operation of the heat pump heat source unit 3 in hot water storage mode, the hot water is heated by absorbing heat from the outside air (the air in the storage section S). Generally, the operating efficiency of the heat pump heat source unit 3 improves as the outside air temperature increases and as the temperature of the hot water after heating decreases. In order to perform the heating operation with high operating efficiency, the operating capacity of the heat pump heat source unit 3 is set according to the outside air temperature and the heat pump inlet water temperature.

[0030] A hot water supply remote control 17 installed in the room (for example, in the bathroom) is communicatively connected to the control unit 5. The hot water supply remote control 17 has an operation unit for performing various operations and a display unit for displaying various information, but may also have a touch panel in which the operation unit and display unit are integrated. By operating this hot water supply remote control 17, various operations can be started and stopped, and various settings such as the hot water supply temperature setting can be made. In addition to the hot water supply remote control 17 in the bathroom, the hot water storage and hot water supply device 1 may have multiple operation terminals, such as a kitchen remote control installed in the kitchen, for example.

[0031] As shown in Fig. 4, the heat pump heat source unit 3 is configured by connecting a compressor 31, a condensing heat exchanger 32, an expansion valve 33, and an evaporative heat exchanger 34 via a refrigerant circuit 35. In a heating operation, the heat pump heat source unit 3 compresses the refrigerant sealed in the refrigerant circuit 35 in the compressor 31 to a high temperature, and heats the refrigerant in the condensing heat exchanger 32 by exchanging heat between the high-temperature refrigerant and hot water in the hot water storage tank 2, which is supplied by driving the pump 7. The refrigerant, whose temperature has decreased after the heat exchange, expands in the expansion valve 33 to a temperature lower than the outside air, absorbs heat from the outside air in the evaporative heat exchanger 34, and is then introduced back into the compressor 31.

[0032] The evaporative heat exchanger 34 is equipped with an outdoor air temperature sensor 34a (air temperature detection means) that detects the outdoor air temperature, an outdoor air humidity sensor 34b (humidity detection means) that detects the outdoor air humidity, and a blower fan 36. A heat pump inlet water temperature sensor 32a that detects the inlet temperature of the hot water is attached to the hot water inlet side of the condenser heat exchanger 32 to which the supply passage 8 is connected. The heat pump heat source unit 3 also has an auxiliary control unit 37 that controls the compressor 31, expansion valve 33, blower fan 36, etc. The auxiliary control unit 37 is communicably connected to the control unit 5, which is the main control means of the hot water storage and heating apparatus 1, and controls the heat pump heat source unit 3 according to commands from the control unit 5; however, if the auxiliary control unit 37 is not present, the control unit 5 controls the heat pump heat source unit 3.

[0033] The heat pump heat source unit 3 circulates the refrigerant in the refrigerant circuit 35 through heating operation, and low-temperature refrigerant is introduced into the evaporative heat exchanger 34. When heat is exchanged with outside air, moisture contained in the outside air cools and frost forms on the surface of the evaporative heat exchanger 34, reducing heat exchange efficiency. Therefore, if the outside air temperature detected by the outside air temperature sensor 34a falls below a reference outside air temperature and the difference between the outside air temperature and the refrigerant temperature detected by the outlet temperature sensor of the evaporative heat exchanger exceeds a predetermined reference value, frost is detected and a defrosting operation is performed to remove the frost.

[0034] In defrosting operation, the hot water flowing into the condensing heat exchanger 32 is stopped, the expansion valve 33 is opened, and the high-temperature refrigerant compressed by the compressor 31 is introduced into the evaporative heat exchanger 34, thereby removing the frost from the evaporative heat exchanger 34. In the case where a refrigerant bypass passage 38 branching from the downstream side of the compressor 31 of the refrigerant circuit 35 and connected to the upstream side of the evaporative heat exchanger 34 and a defrost solenoid valve 38a that opens and closes this refrigerant bypass passage 38 are provided, the hot water flowing into the condensing heat exchanger 32 is stopped, the expansion valve 33 is closed, and the defrost solenoid valve 38a is opened to introduce the high-temperature refrigerant into the evaporative heat exchanger 34, thereby removing the frost from the evaporative heat exchanger 34.

[0035] When the outside air temperature falls below the reference outside air temperature, or when the inlet water temperature falls below the reference inlet water temperature, or when both of these conditions are met, the following freeze prevention operation is performed. First, the pump 7 is operated to circulate hot water through the circulation passage consisting of the supply passage 8, the condensing heat exchanger 32, the return passage 9, and the branch passage 9a to prevent freezing. This is done initially without operating the heat pump heat source unit 3. If this circulation of hot water does not prevent freezing, the heat pump heat source unit 3 is operated to warm the hot water and prevent freezing.

[0036] Here, the heat pump heat source unit 3 and the auxiliary heat source unit 4 operate simultaneously in cases where hot water cannot be dispensed from the hot water storage tank 2 because the hot water storage tank 2 has run out of hot water, despite a hot water supply request from the hot water tap F. When the heat pump heat source unit 3 and the auxiliary heat source unit 4 operate simultaneously in this manner, the blower fan 36 of the evaporative heat exchanger 34 of the heat pump heat source unit 3 operates, and as shown by the dashed arrow W in Figure 2, the combustion exhaust gas from the auxiliary heat source unit 4 flows into the storage section S, and after flowing through the storage section S, the combustion exhaust gas is discharged to the outside by the blower fan 36 of the heat pump heat source unit 3.

[0037] In this way, when the combustion exhaust gas from the auxiliary heat source unit 4 flows into the storage unit S, there is a problem that the corrosive substances contained in the combustion exhaust gas corrode the equipment and ventilation doors D1 to D4 inside the storage unit S. Therefore, when the heat pump heat source unit 3 and the auxiliary heat source unit 4 are operated simultaneously, if the combustion load of the auxiliary heat source unit 4 is equal to or greater than a first threshold value, the operation of the heat pump heat source unit 3 is limited according to the combustion load.

[0038] Then, when the combustion load of the auxiliary heat source unit 4 becomes equal to or greater than a second threshold value that is greater than the first threshold value, the operation of the heat pump heat source unit 3 is stopped. The first threshold value is a combustion load of 30%, and the second threshold value is a combustion load of 60%. Note that the operation of the heat pump heat source unit 3 is not restricted when the heat pump heat source unit 3 is performing anti-freeze operation or defrost operation.

[0039] The heat pump heat source unit output limiting control when the heat pump heat source unit and auxiliary heat source unit are operating simultaneously will be described with reference to the flowchart in Figure 5. The flowchart for this heat pump heat source unit output limiting control and the map data shown in Figure 6 are stored in advance in the control device 5. In the flowchart, Si (i = 1, 2, ...) indicates each step, and hereinafter "HP" means "heat pump."

[0040] When this heat pump heat source unit output limiting control is started, in S1 it is determined whether simultaneous operation of the HP heat source unit 3 and the auxiliary heat source unit 4 is necessary. This determination is made based on the operating state of the HP heat source unit 3 and the operating state of the auxiliary heat source unit 4. If the determination in S1 is No, the process returns to S1, and if the determination in S1 is Yes, the process proceeds to S2, where it is determined whether the HP heat source unit 3 is in anti-freeze operation or defrost operation. This determination is made based on the control state of the expansion valve 33 or the anti-freeze valve 38a in the auxiliary control unit 37.

[0041] If the determination in S2 is Yes, simultaneous operation of the HP heat source unit 3 and the auxiliary heat source unit 4 is permitted in S4, and then the process returns to S1. If the determination in S2 is No, then in S3 it is determined whether the combustion load L of the auxiliary heat source unit 4 is less than 30% (first threshold), and if L<30%, there is no need to limit the output of the HP heat source unit 3, so the process proceeds to S4, simultaneous operation is permitted, and then the process returns. The combustion load L can be calculated from the flow rate of fuel gas supplied to the auxiliary heat source unit 4.

[0042] If the determination in S3 is No, then in S5 it is determined whether 30%≦L<60% (second threshold), and if the determination is Yes, the output of the HP heat source unit 3 is limited according to the combustion load L based on the map M shown in Figure 6, and then the process returns.

[0043] In this way, when 30%≦L<60%, the output of the HP heat source unit 3 is limited according to the combustion load L so that the output of the HP heat source unit 3 decreases as the combustion load L increases.This reduces the inflow gas flow rate of the combustion exhaust gas from the auxiliary heat source unit 4 into the storage unit S, reduces the amount of corrosive substances contained in the combustion exhaust gas that flow into the storage unit S, and minimizes corrosion of the equipment and doors D1 to D4 within the storage unit S.

[0044] If the determination in S5 is No, the process proceeds to S7, where it is determined whether 60%≦L, and if the determination is Yes, the process proceeds to S8, where the operation of the HP heat source unit 3 is stopped and then the process returns. Note that if the determination in S5 is No, 60%≦L is always true, so step S7 may be omitted.

[0045] The operation and effects of the hot water storage and boiler apparatus 1 described above will now be described. This hot water storage and heating apparatus 1 is configured as a three-piece unit consisting of an HP heat source unit 3, an auxiliary heat source unit 4, and a hot water storage tank 2, and is installed in a housing unit S (pipe space). When the HP heat source unit 3 and the auxiliary heat source unit 4 are operated simultaneously, the output of the HP heat source unit 3 is not limited if the combustion load L of the auxiliary heat source unit 4 is less than 30%, so the hot water storage function of the HP heat source unit 3 can be maintained.

[0046] When the combustion load L of the auxiliary heat source unit 4 is 30% or more and less than 60%, the output of the HP heat source unit 3 is limited according to the combustion load L based on map M, so that the output is limited while retaining the hot water storage function of the HP heat source unit 3, thereby limiting the amount of combustion exhaust gas flowing into the storage section S. When the combustion load L is 60% or more, the operation of the HP heat source unit 3 is stopped, so that the inflow of combustion exhaust gas into the accommodation section S can be prevented.

[0047] During anti-freeze operation or defrost operation, simultaneous operation of the HP heat source unit 3 and the auxiliary heat source unit 4 is permitted, so that the HP heat source unit 3 can be prevented from freezing and frost can be removed reliably. Furthermore, simultaneous operation of the HP heat source unit 3 and the auxiliary heat source unit 4 can be permitted during freeze prevention operation or defrost operation because freeze prevention operation and defrost operation operate the blower fan 36 at low speed or are operated without turning on the blower fan 36.

[0048] Next, an example of modifying the above embodiment will be described. 1) The characteristics shown in the map M are merely an example and are not limited to these characteristics. Instead of a map, an arithmetic expression may be used in which the combustion load and the output of the HP heat source unit 3 are used as parameters.

[0049] 2) The combustion load L may be calculated based on the flow rate and gas pressure of the fuel gas supplied to the auxiliary heat source unit 4, or may be calculated based on the number of combustion stages and gas pressure of the auxiliary heat source unit 4. 3) The second threshold value is set to a combustion load of 60%. However, the second threshold value may be set to a combustion load of 70%. 4) In addition, a person skilled in the art can implement the present invention in a form in which various modifications are added to the above-described embodiment without departing from the spirit of the present invention, and the present invention includes such modifications. [Explanation of symbols]

[0050] 1: Hot water storage unit 2: Hot water tank 3: Heat pump heat source machine 4:Auxiliary heat source machine 5: Control section 31: Compressor 32: Condensing heat exchanger 33: Expansion valve 34: Evaporative heat exchanger 35: Refrigerant circuit 36: Blower fan 37: Auxiliary control section 38 : Refrigerant bypass passage 38a: Defrost solenoid valve D1~D4: Doors OP2~OP4: Opening S: Storage section (pipe space)

Claims

1. A hot water storage and hot water supply device equipped with a control unit that controls a hot water storage operation that heats hot water and stores it in a hot water storage tank, wherein a heat pump heat source that heats hot water in the hot water storage operation, a combustion-type auxiliary heat source, and the hot water storage tank are installed in a storage section with a ventilation door in a building. A hot water storage and heating device characterized in that, when the heat pump heat source unit and the auxiliary heat source unit are operating simultaneously, the operation of the heat pump heat source unit is limited when the combustion load of the auxiliary heat source unit is equal to or greater than a first threshold value.

2. 2. The hot water storage and heating device according to claim 1, wherein operation of the heat pump heat source unit is stopped when the combustion load of the auxiliary heat source unit becomes equal to or greater than a second threshold value that is greater than the first threshold value.

3. 3. The hot water storage tank heater according to claim 1, wherein the operation of the heat pump heat source unit is not limited when the heat pump heat source unit is performing a freeze prevention operation or a defrosting operation.

4. 3. The hot water storage tank heater according to claim 2, wherein the first threshold value is a combustion load of 30%, and the second threshold value is a combustion load of 60%.

Images