JP6102793B2 - Heat pump type hot water heater - Google Patents

Description

  The present invention relates to a heat pump type heating and hot water supply apparatus that performs heat exchange between a refrigerant and water.

  2. Description of the Related Art Conventionally, there is known a heat pump type heating and hot water supply apparatus that performs heating and hot water supply using hot water generated by performing heat exchange between a refrigerant and water. Among such heat pump type heating and hot water supply apparatuses, a compressor, a water refrigerant heat exchanger that performs heat exchange between the refrigerant and water, an expansion valve, and a heat source side heat exchanger are sequentially connected by a refrigerant pipe. Having a plurality of heat pump circuits and a hot water supply circuit for circulating hot water heated by each water refrigerant heat exchanger to a heating load such as a floor heating panel or a bathroom heating device or a hot water supply load such as a hot water storage tank by a circulation pump (For example, refer to Patent Document 1).

  In the heat pump type heating and hot water supply apparatus described in Patent Document 1, hot water is supplied from at least one heat pump circuit among a plurality of heat pump circuits to the hot water supply load, and hot water is supplied from other heat pump circuits to the heating load. And in this heat pump type heating hot-water supply apparatus, it is possible to drive | work a hot-water supply load and a heating load simultaneously.

JP-A-2005-337626

  For example, a hot water storage tank that stores hot water heated to a predetermined temperature may be provided as a hot water supply load. In the hot water storage tank, there is a case where a boiling operation is performed in which the water in the hot water storage tank is heated to a predetermined target temperature by using late-night power cheaper than daytime. In boiling operation, since the target temperature is high (for example, 55 ° C. or 60 ° C.), it is installed in a water refrigerant heat exchanger that heats hot water that is installed outside the hot water tank and is supplied to the hot water tank, or in the hot water tank. The condensing pressure in the heat exchanging unit that directly installs heat between the water in the hot water storage tank and the refrigerant is increased.

  When the condensation pressure increases, the refrigerant tends to be biased toward the heat source side heat exchanger. In this state, if the water in the hot water storage tank rises to the target temperature and the boiling operation is completed and the heat pump circuit on the hot water supply load side is stopped, a large amount of liquid refrigerant may stagnate in the heat source side heat exchanger. . If a heat pump circuit on the hot water supply load side is restarted in a state where a large amount of liquid refrigerant has stagnated in the heat source side heat exchanger, a so-called liquid back into which the liquid refrigerant is sucked into the compressor occurs, and the compressor is damaged. There was a fear.

  An object of the present invention is to solve the above-described problems and to provide a heat pump type heating and hot water supply apparatus capable of preventing liquid back to the compressor.

  This invention solves the above-mentioned subject, The heat pump type heating hot-water supply apparatus of this invention has a some heat pump circuit, a heating hot water circuit, and a hot-water supply refrigerant circuit, Comprising: A some heat pump circuit Respectively, a compressor, a water refrigerant heat exchanger, a flow rate adjusting means, and a heat source side heat exchanger are sequentially connected by refrigerant piping, and at least one of the plurality of heat pump circuits is a heat pump circuit for hot water supply. In addition, heat pump circuits other than those constituting the hot water supply heat pump circuit are used as the heating heat pump circuit. The heating / warming water circuit is configured by sequentially connecting a heating load, an auxiliary water / refrigerant heat exchanger, a plurality of water / refrigerant heat exchangers, and a circulation pump via a hot water supply pipe. The hot water supply heat pump circuit is configured to be connected by a forward refrigerant pipe through which refrigerant flowing into the hot water supply load flows and a return refrigerant pipe through which refrigerant flowing out of the hot water supply load flows. Further, in the hot water supply heat pump circuit, the auxiliary water refrigerant heat exchanger is connected to the heat source side heat exchanger and the compressor so that the refrigerant flowing out of the heat source side heat exchanger flows through the auxiliary water refrigerant heat exchanger and is sucked into the compressor. And are connected by refrigerant piping. Then, after operating the hot water supply heat pump circuit and performing the hot water supply operation with the hot water supply load, when stopping the hot water supply heat pump circuit and then restarting the hot water supply heat pump circuit, the heating heat pump circuit is started first, After the water circulating in the circuit is raised to a predetermined temperature, the hot water supply heat pump circuit is started, and the auxiliary water refrigerant heat exchanger flows out of the water circulating in the heating hot water circuit and the heat source side heat exchanger of the hot water supply heat pump circuit Heat exchange with the refrigerant is performed.

  The heat pump type heating and hot water supply apparatus of the present invention is a state where only the hot water supply heat pump circuit is operated, and when the hot water supply heat pump circuit is stopped and then restarted, the hot water circulating in the heating hot water circuit and the hot water supply heat pump circuit The refrigerant flowing out of the heat source side heat exchanger in the heat exchange is exchanged in the auxiliary water refrigerant heat exchanger. As a result, the liquid refrigerant sleeping in the heat source side heat exchanger is evaporated by exchanging heat with the hot water flowing through the heating hot water circuit before being sucked into the compressor, thereby preventing liquid back to the compressor.

It is a block diagram of the heat pump type heating hot-water supply apparatus in embodiment of this invention, and represents the flow of a refrigerant | coolant and warm water when only an indoor unit is drive | operating. It is a block diagram of the heat pump type heating hot-water supply apparatus in embodiment of this invention, and represents the flow of a refrigerant | coolant and warm water when performing the operation | movement of an indoor unit and the boiling operation of a hot water storage tank simultaneously. It is a block diagram of the heat pump type heating hot water supply apparatus in embodiment of this invention, and represents the flow of a refrigerant | coolant and warm water when performing only the heating operation of a hot water storage tank. It is a time when only heating operation is performed after the boiling operation is stopped, and the flow of the refrigerant and hot water in a state where only the first heat pump circuit is activated. FIG. 5 is a diagram showing the flow of refrigerant and hot water when only heating operation is performed after the boiling operation is stopped and the second heat pump circuit is also activated to exchange heat between hot water and refrigerant in the auxiliary heat exchanger. is there.

  Embodiments of the present invention will be described below in detail with reference to the accompanying drawings. The embodiment includes an indoor unit that is a heating load and a hot water storage tank that is a hot water supply load in the present invention, and performs heating by circulating hot water that has been heat-exchanged with the refrigerant in a water-refrigerant heat exchanger to the indoor unit. In addition, a heat pump heating and hot water supply apparatus that heats the water stored in the hot water storage tank by circulating the refrigerant in the heat exchange section installed in the hot water storage tank will be described as an example. The present invention is not limited to the following embodiments, and can be variously modified without departing from the gist of the present invention.

  FIG. 1 shows a configuration of a heat pump type heating and hot water supply apparatus according to the present invention. This heat pump type heating and hot water supply apparatus 100 includes a first heat pump circuit 10a that is a heat pump circuit for heating, a second heat pump circuit 10b that is a heat pump circuit for hot water supply, a heating and hot water circuit 30, and a hot water supply refrigerant circuit 40. Yes. The first heat pump circuit 10a and the second heat pump circuit 10b can be operated independently. The second heat pump circuit 10b is a hot water supply heat pump circuit in the present invention.

  In the first heat pump circuit 10a, a compressor 1a, a water refrigerant heat exchanger 2a, an expansion valve 3a that is a flow rate adjusting means, a heat source side heat exchanger 4a, and an accumulator 5a are sequentially connected by a refrigerant pipe 11a. Configured. The compressor 1a is a variable-capacity compressor that can vary the driving capability by being driven by a motor (not shown) whose rotation speed is controlled by an inverter. The water-refrigerant heat exchanger 2a has a refrigerant-side flow path 2aa connected to the refrigerant pipe 11a, and a water-side flow path 2ab connected to a hot water pipe 31 of the heating / warming water circuit 30 described later. Heat is exchanged between the refrigerant flowing through 2aa and the water flowing through the water-side flow path 2ab. The expansion valve 3a is an electronic expansion valve, and the amount of refrigerant flowing into the heat source side heat exchanger 4a is adjusted by adjusting the opening thereof. The heat source side heat exchanger 4a exchanges heat between the refrigerant and the air flowing into the heat source side heat exchanger 4a by the rotation of the outdoor fan 6a disposed in the vicinity of the heat source side heat exchanger 4a. The accumulator 5a separates the refrigerant flowing in from the heat source side heat exchanger 4a into liquid refrigerant and gas refrigerant, and causes only the gas refrigerant to be sucked into the compressor 1a.

  The first heat pump circuit 10a includes a discharge temperature sensor 51a, a refrigerant temperature sensor 52a, a heat exchange temperature sensor 53a, and an outside air temperature sensor 54a. The discharge temperature sensor 51a is provided in the refrigerant pipe 11a near the refrigerant discharge side of the compressor 1a, and detects the temperature of the refrigerant discharged from the compressor 1a. The refrigerant temperature sensor 52a is provided in the refrigerant pipe 11a between the water refrigerant heat exchanger 2a and the expansion valve 3a, and detects the temperature of the refrigerant flowing out from the water refrigerant heat exchanger 2a. The heat exchanger temperature sensor 53a is provided in the refrigerant pipe 11a between the expansion valve 3a and the heat source side heat exchanger 4a, and detects the temperature of the refrigerant flowing into the heat source side heat exchanger 5a. The outside air temperature sensor 54a is disposed in the vicinity of the heat source side heat exchanger 5a and detects an outside air temperature that is an outdoor temperature.

  The second heat pump circuit 10b includes a compressor 1b, a first three-way valve 7, a water / refrigerant heat exchanger 2b, a second three-way valve 8, an expansion valve 3b as a flow rate adjusting means, and a heat source side heat exchanger 4b. The third three-way valve 9, the auxiliary water refrigerant heat exchanger 23, and the accumulator 5b are sequentially connected by the refrigerant pipe 11b. The compressor 1b is a variable capacity compressor capable of varying the driving capacity by being driven by a motor (not shown) whose rotation speed is controlled by an inverter. The water-refrigerant heat exchanger 2b has a refrigerant-side flow path 2ba connected to the refrigerant pipe 11b and a water-side flow path 2bb connected to a hot water pipe 31 of the heating / warming water circuit 30 described later, Heat exchange is performed between the refrigerant flowing through 2ba and the water flowing through the water-side flow path 2bb. The expansion valve 3b is an electronic expansion valve, and the amount of refrigerant flowing into the heat source side heat exchanger 4b is adjusted by adjusting the opening thereof. The heat source side heat exchanger 4b exchanges heat between the refrigerant and the air flowing into the heat source side heat exchanger 4b by the rotation of the outdoor fan 6b disposed in the vicinity of the heat source side heat exchanger 4b. The auxiliary water refrigerant heat exchanger 23 includes a refrigerant side flow path 23a connected to the refrigerant pipe 11b and a water side flow path 23b connected to a hot water pipe 31 of the heating / warming water circuit 30 described later. Heat is exchanged between the refrigerant flowing through the channel 23a and the water flowing through the water-side channel 23b. The accumulator 5b separates the refrigerant flowing in from the heat source side heat exchanger 4b into liquid refrigerant and gas refrigerant, and causes only the gas refrigerant to be sucked into the compressor 1b.

  The first three-way valve 7 has three ports, port a, port b, and port c. The port a is connected to the refrigerant discharge side of the compressor 1b by a refrigerant pipe 11b. The port b is connected to one end of the refrigerant side flow path 2ba of the water refrigerant heat exchanger 2b by a refrigerant pipe 11b. One end of a forward refrigerant pipe 41 to be described later is connected to the port c. In FIG. 1, the first three-way valve 7 is in a state where the port c is closed (in FIG. 1, the closed port c is painted black), and the port a and the port b communicate with each other.

  The second three-way valve 8 has three ports, port d, port e, and port f. The port d is connected to the other end of the refrigerant side flow path 2ba of the water refrigerant heat exchanger 2b by a refrigerant pipe 11b. The port e is connected to the expansion valve 3b and the refrigerant pipe 11b. One end of a return refrigerant pipe 42 to be described later is connected to the port f. In FIG. 1, the second three-way valve 8 is in a state where the port f is closed (in FIG. 1, the closed port f is painted black), and the port d and the port e communicate with each other.

  The third three-way valve 9 has three ports, port k, port m, and port n. The port k is connected to the refrigerant outflow side of the heat source side heat exchanger 4b by the refrigerant pipe 11b. The port m is connected to one end of the refrigerant side flow path 23a of the auxiliary water refrigerant heat exchanger 23 by the refrigerant pipe 11b. One end of the first bypass pipe 11c that bypasses the auxiliary water refrigerant heat exchanger 23 is connected to the port n, and the other end of the first bypass pipe 11c is connected to the refrigerant side flow path 23a of the auxiliary water refrigerant heat exchanger 23. Is connected to a refrigerant pipe 11b that connects the other end of the refrigerant to the refrigerant inflow side of the accumulator 5b. In FIG. 1, the third three-way valve 9 is in a state where the port m is closed (in FIG. 1, the closed port m is painted black), and the port k and the port n communicate with each other.

  The second heat pump circuit 10b includes a discharge temperature sensor 51b, a refrigerant temperature sensor 52b, a heat exchange temperature sensor 53b, an outside air temperature sensor 54b, and an auxiliary water refrigerant heat exchange temperature sensor 57. The discharge temperature sensor 51b is provided in the refrigerant pipe 11b near the refrigerant discharge port of the compressor 1b, and detects the temperature of the refrigerant discharged from the compressor 1b. The refrigerant temperature sensor 52b is provided in the refrigerant pipe 11b between the water refrigerant heat exchanger 2b and the expansion valve 3b, and detects the temperature of the refrigerant flowing out of the water refrigerant heat exchanger 2b. The heat exchanger temperature sensor 53b is provided in the refrigerant pipe 11b between the expansion valve 3b and the heat source side heat exchanger 4b, and detects the temperature of the refrigerant flowing into the heat source side heat exchanger 5b. The outside air temperature sensor 54b is disposed in the vicinity of the heat source side heat exchanger 5b and detects the outside air temperature that is an outdoor temperature. The auxiliary water heat exchanger temperature sensor 57 is provided in the refrigerant pipe 11b between the auxiliary water refrigerant heat exchanger 23 and the accumulator 5b, and detects the temperature of the refrigerant flowing out of the auxiliary water refrigerant heat exchanger 23.

  The heating hot water circuit 30 includes an indoor unit 21 that is a heating load, an auxiliary water refrigerant heat exchanger 23, a water refrigerant heat exchanger 2a, a fourth three-way valve 28, a water refrigerant heat exchanger 2b, and a circulation pump 22. Are sequentially connected by a hot water supply pipe 31. The indoor unit 21 includes a floor heating panel and a radiator, and warm water flowing through the indoor unit 21 heats the air in the room in which the indoor unit 21 is installed, thereby heating the room. The auxiliary water refrigerant heat exchanger 23 includes a water side flow path 23b connected to the hot water supply pipe 31, and a refrigerant side flow path 23a connected to the refrigerant pipe 11b of the second heat pump circuit 11b described above. Heat exchange is performed between the refrigerant flowing through the flow path 23a and the water flowing through the water-side flow path 23b. The water refrigerant heat exchangers 2a and 2b are disposed between the circulation pump 22 and the auxiliary water refrigerant heat exchanger 23, and the water side flow path 2ab of the water refrigerant heat exchanger 2a and the water side of the water refrigerant heat exchanger 2b. The flow paths 2bb are connected to the hot water supply pipes 31, respectively. The circulation pump 22 is a variable capacity pump, and the hot water circulates in the heating / hot water circuit 30 when the circulation pump 22 is driven.

  The fourth three-way valve 28 has three ports, port g, port h, and port j. The port g is connected to the water-side flow path 2ab of the water-refrigerant heat exchanger 2a by the hot water supply pipe 31. The port h is connected to the water-side flow path 2bb of the water-refrigerant heat exchanger 2b by a hot water supply pipe 31. One end of the second bypass pipe 32 that bypasses the water refrigerant heat exchanger 2b is connected to the port j, and the other end of the second bypass pipe 32 is between the water refrigerant heat exchanger 2b and the circulation pump 22. It is connected to the hot water supply pipe 31. In FIG. 1, the fourth three-way valve 28 is in a state where the port j is closed (in FIG. 1, the closed port j is painted black), and the port g and the port h are in communication.

  The heating / warming water circuit 30 includes a first forward temperature sensor 55 and a second forward temperature sensor 56. The first forward temperature sensor 55 is provided in the hot water supply pipe 31 in the vicinity of the water refrigerant heat exchanger 2a on the fourth three-way valve 28 side, and detects the first forward temperature that is the water temperature flowing out from the water refrigerant heat exchanger 2a. The second forward temperature sensor 56 is provided in the hot water supply pipe 31 in the vicinity of the water refrigerant heat exchanger 2b on the circulation pump 22 side, and detects the second forward temperature, which is the water temperature flowing out from the water refrigerant heat exchanger 2b.

  The hot water supply refrigerant circuit 40 includes a first three-way valve 7, a hot water storage tank 24 that is a hot water supply load, and a second three-way valve 8 that are connected by a forward refrigerant pipe 41 and a return refrigerant pipe 42. The hot water storage tank 24 includes a heat exchanging unit 25, a water inlet 26, a hot water inlet 27, and a hot water sensor 58. The heat exchange section 25 has a refrigerant pipe formed in a spiral shape, and is disposed below the hot water storage tank 24. The lower end of the heat exchange unit 25 is connected to the other end of the outgoing refrigerant pipe 41, and the upper end of the heat exchange unit 25 is connected to the other end of the return refrigerant pipe 42. The water inlet 26 is provided below the hot water storage tank 24. A water pipe (not shown) is directly connected to the water inlet 26, and water is supplied from the water pipe through the water inlet 26 into the hot water storage tank 24. The hot water supply port 27 is provided in the upper part of the hot water storage tank 24. The hot water supply port 27 is connected to a hot water pipe connected to a bathtub, a washbasin faucet and the like (not shown), and hot water stored in the hot water storage tank 24 is supplied from the hot water supply port 27 to the bathtub and the washbasin faucet. The hot water storage sensor 58 detects the temperature of the hot water stored in the hot water storage tank 24. Further, as described above, one end of the forward refrigerant pipe 41 is connected to the port c of the first three-way valve 7, and one end of the return refrigerant pipe 42 is connected to the port f of the second three-way valve 8.

  Next, the operation | movement operation | movement of the heat pump type heating hot-water supply apparatus 100 in this embodiment is demonstrated. First, referring to FIG. 1, when only the heating operation by the indoor unit 21 is performed, the operation of each component device in the first heat pump circuit 10a, the second heat pump circuit 10b, and the heating / warming water circuit 30 and The accompanying refrigerant and hot water flow will be described. Next, referring to FIG. 2, the first heat pump circuit 10 a in the case where the heating operation by the indoor unit 21 and the boiling operation for boiling the temperature of the water stored in the hot water storage tank 24 to a predetermined temperature are simultaneously performed. The operation of each component device in the second heat pump circuit 10b, the heating / hot water circuit 30, and the hot water supply / refrigeration circuit 40, and the flow of the refrigerant and hot water associated therewith will be described. Next, referring to FIG. 3, the operation of each component device in the second heat pump circuit 10b and the hot water supply refrigerant circuit 40 when only the boiling operation in the hot water storage tank 24 is performed, and the accompanying refrigerant and hot water The flow will be described. Finally, with reference to FIG. 4 and FIG. 5, when the heat pump type heating / hot water supply device 100 is started in a state where only the heating operation described above is performed and only the heating operation is performed after the boiling operation is stopped, The operation of each component device in the 1 heat pump circuit 10a, the second heat pump circuit 10b, and the heating / warming water circuit 30, and the flow of refrigerant and warm water associated therewith will be described. 1 to 5, the arrows indicate the directions in which the refrigerant and hot water flow in each circuit. In each three-way valve, the open port is outlined and the closed port is painted black.

  First, the case where only the heating operation by the indoor unit 21 is performed will be described with reference to FIG. As shown in FIG. 1, when only the heating operation is performed by the heat pump heating / hot water supply apparatus 100, the first three-way valve 7 of the second heat pump circuit 10b has the port c closed so that the ports a and b communicate with each other. It is supposed to be in a state to do. The second three-way valve 8 of the second heat pump circuit 10b is in a state in which the port f is closed and the port d and the port e communicate with each other. The third three-way valve 9 of the second heat pump circuit 10b is in a state in which the port m is closed and the port k and the port n communicate with each other. The fourth three-way valve 28 of the heating / warming water circuit 30 is in a state in which the port j is closed and the port g and the port h communicate with each other. And compressor 1a, 1b of the 1st heat pump circuit 10a and the 2nd heat pump circuit 10b and the circulation pump 22 of the heating hot water circuit 30 are driven.

  In the following description, the heating operation set temperature Ti set by the user in the indoor unit 21 is 24 ° C., and in order to realize this set temperature Ti, the target that is the target value of the hot water temperature flowing into the indoor unit 21 A case where the hot water temperature Tt is 40 ° C. will be described as an example.

  In the first heat pump circuit 10a and the second heat pump circuit 10b, the refrigerant compressed and discharged by the compressors 1a and 1b flows into the refrigerant side flow paths 2aa and 2ba of the water refrigerant heat exchangers 2a and 2b. The refrigerant flowing into the refrigerant side flow paths 2aa and 2ba of the water refrigerant heat exchangers 2a and 2b is condensed by performing heat exchange with water flowing through the water side flow paths 2ab and 2bb of the water refrigerant heat exchangers 2a and 2b, It flows out from water refrigerant heat exchanger 2a, 2b.

  The refrigerant that has flowed out of the water-refrigerant heat exchangers 2a and 2b is decompressed and flows into the heat source side heat exchangers 4a and 4b when passing through the expansion valves 3a and 3b. The refrigerant flowing into the heat source side heat exchangers 4a and 4b evaporates by exchanging heat with the air flowing into the heat source side heat exchangers 4a and 4b by the rotation of the outdoor fans 6a and 6b, and the heat source side heat exchangers 4a and 4b. It flows out from 4b. In the first heat pump circuit 10a, the refrigerant flowing out from the heat source side heat exchanger 4a is sucked into the compressor 1a through the accumulator 5a and compressed again. In the second heat pump circuit 10b, the refrigerant flowing out from the heat source side heat exchanger 4b flows into the port k of the third three-way valve 9, flows out from the port n into the first bypass pipe 11c, and is compressed through the accumulator 5b. It is sucked into the machine 1b and compressed again.

  On the other hand, in the heating / warming water circuit 30, the water flowing into the water-side flow path 2ab of the water-refrigerant heat exchanger 2a by driving the circulation pump 22 exchanges heat with the refrigerant flowing through the refrigerant-side flow path 2aa of the water-refrigerant heat exchanger 2a. And heated to a first predetermined temperature T1 (for example, 30 ° C.) lower than the target hot water temperature Tt, and flows out of the water-refrigerant heat exchanger 2a. The hot water flowing out from the water refrigerant heat exchanger 2a flows into the water side flow path 2bb of the water refrigerant heat exchanger 2b via the fourth three-way valve 28.

  The water flowing into the water-side flow path 2bb of the water-refrigerant heat exchanger 2b is further heated by exchanging heat with the refrigerant flowing through the refrigerant-side flow path 2ba of the water-refrigerant heat exchanger 2b, so that the second predetermined temperature T2 (= It becomes hot water having a target hot water temperature Tt: 40 ° C. and flows out of the water-refrigerant heat exchanger 2b. The hot water flowing out of the water-refrigerant heat exchanger 2b flows into the indoor unit 21 via the circulation pump 22, and the hot water flowing into the indoor unit 21 dissipates heat, thereby heating the room where the indoor unit 21 is installed. The And the warm water which flowed out from the indoor unit 21 flows into the water refrigerant heat exchangers 2a and 2b via the auxiliary water refrigerant heat exchanger 23, and is heated again.

  Here, in the first heat pump circuit 10a, the temperature of the water flowing out from the water-refrigerant heat exchanger 2a becomes the first predetermined temperature T1 described above, that is, the hot water temperature detected by the first forward temperature sensor 55 is the first temperature. 1 The rotational speed of the compressor 1a, the opening degree of the expansion valve 3a, and the rotational speed of the outdoor fan 6a are controlled so that the predetermined temperature T1 is obtained. Further, in the second heat pump circuit 10b, the temperature of the water flowing out from the water-refrigerant heat exchanger 2b becomes the above-mentioned second predetermined temperature T2, that is, the hot water temperature detected by the second forward temperature sensor 56 is the second temperature. The rotational speed of the compressor 1b, the opening degree of the expansion valve 3b, and the rotational speed of the outdoor fan 6b are each controlled so as to reach the predetermined temperature T2.

  As described above, when only the heating operation is performed in the heat pump heating / hot water supply apparatus 100, the first heat pump circuit 10a and the second heat pump circuit 10b are operated, and the hot water temperature flowing into the indoor unit 21 is set as the target hot water temperature. Raise to Tt.

  Next, the case where the heating operation by the indoor unit 21 and the boiling operation in the hot water storage tank 24 are performed simultaneously will be described with reference to FIG. As shown in FIG. 2, when the heating operation by the indoor unit 21 and the boiling operation in the hot water storage tank 24 are simultaneously performed, the first three-way valve 7 of the second heat pump circuit 10b is closed when the port b is closed. And port c communicate with each other. The second three-way valve 8 of the second heat pump circuit 10b is in a state where the port d is closed and the port e and the port f are in communication. The third three-way valve 9 of the second heat pump circuit 10b is in a state in which the port m is closed and the port k and the port n communicate with each other. The fourth three-way valve 28 of the heating / warming water circuit 30 is in a state in which the port h is closed and the port g and the port j communicate with each other. And compressor 1a, 1b of the 1st heat pump circuit 10a and the 2nd heat pump circuit 10b and the circulation pump 22 of the heating hot water circuit 30 are driven.

  In the following description, the heating operation set temperature Ti set by the user in the indoor unit 21 is 24 ° C., and in order to realize this set temperature Ti, the target that is the target value of the hot water temperature flowing into the indoor unit 21 is set. The case where the hot water temperature Tt is 40 ° C. and the boiling temperature Tb, which is the target temperature when boiling the water stored in the hot water storage tank 24, is 60 ° C. will be described as an example.

  About the flow of the refrigerant in the 1st heat pump circuit 10a, since it is the same as the case where the heating operation mentioned above is performed, explanation is omitted. In the second heat pump circuit 10 b, the refrigerant compressed and discharged by the compressor 1 b flows from the refrigerant pipe 11 b through the first three-way valve 7 through the refrigerant pipe 41 and flows into the heat exchange unit 25 of the hot water storage tank 24. . The refrigerant that has flowed into the heat exchange unit 25 exchanges heat with the water stored in the hot water storage tank 24 and flows out of the heat exchange unit 25. The refrigerant that has flowed out of the heat exchange section 25 flows through the return refrigerant pipe 42 and flows into the refrigerant pipe 11b through the second three-way valve 8.

  The refrigerant flowing into the refrigerant pipe 11b is reduced in pressure when passing through the expansion valve 3b and flows into the heat source side heat exchanger 4b. The refrigerant flowing into the heat source side heat exchanger 4b evaporates by exchanging heat with the air flowing into the heat source side heat exchanger 4b by the rotation of the outdoor fan 6b, and flows out from the heat source side heat exchanger 4b. The refrigerant flowing out from the heat source side heat exchanger 4b flows into the port k of the third three-way valve 9, flows out from the port n into the first bypass pipe 11c, and is sucked into the compressor 1b through the accumulator 5b. It is compressed again.

  On the other hand, in the heating / warming water circuit 30, the water flowing into the water-side flow path 2ab of the water-refrigerant heat exchanger 2a by driving the circulation pump 22 exchanges heat with the refrigerant flowing through the refrigerant-side flow path 2aa of the water-refrigerant heat exchanger 2a. Is heated to become hot water at a second predetermined temperature T2 (= target hot water temperature Tt: 40 ° C.) and flows out of the water-refrigerant heat exchanger 2a. The hot water flowing out from the water-refrigerant heat exchanger 2a flows into the second bypass pipe 32 from the hot water pipe 31 via the fourth three-way valve 28, and flows into the hot water pipe 31 again from the second bypass pipe 32. It flows so as to bypass the refrigerant heat exchanger 2b.

  The warm water that has flowed into the warm water pipe 31 from the second bypass pipe 32 flows into the indoor unit 21, and the warm water that has flowed into the indoor unit 21 dissipates heat, thereby heating the room in which the indoor unit 21 is installed. And the warm water which flowed out from the indoor unit 21 flows in into the water refrigerant | coolant heat exchanger 2a via the auxiliary water refrigerant | coolant heat exchanger 23, and is heated again.

  Here, in the first heat pump circuit 10a, the temperature of the water flowing out from the water-refrigerant heat exchanger 2a becomes the above-mentioned second predetermined temperature T2, that is, the hot water temperature detected by the first forward temperature sensor 55 is the first temperature. 2 The rotational speed of the compressor 1a, the opening degree of the expansion valve 3a, and the rotational speed of the outdoor fan 6a are controlled so that the predetermined temperature T2 is reached. Further, in the second heat pump circuit 10b, the rotation of the compressor 1b is performed so that the temperature of the hot water stored in the hot water storage tank 24, that is, the temperature of the hot water detected by the hot water storage sensor 58 becomes the above-described boiling temperature Tb. The number, the opening degree of the expansion valve 3b, and the rotational speed of the outdoor fan 6b are respectively controlled.

  As described above, in the heat pump type heating and hot water supply apparatus 100, the heating operation by the indoor unit 21 is performed by operating the first heat pump circuit 10a, and at the same time, the boiling operation in the hot water storage tank 24 is performed by the second heat pump circuit. It can be executed by driving 10b.

  When the temperature of the hot water stored in the hot water storage tank 24 reaches the boiling temperature Tb, the boiling operation is terminated, and the heat pump type hot water heater 100 is in the state shown in FIG. 1, that is, the first heat pump circuit 10a. It switches to the state which operates the 2nd heat pump circuit 10b, and performs the heating operation by the indoor unit 21. FIG.

  Next, the case where only the boiling operation in the hot water storage tank 24 is performed will be described with reference to FIG. If the hot water stored in the hot water storage tank 24 is reduced by supplying hot water to the faucet or shower of the wash basin during the day or at night, tap water is supplied from the water inlet 26 into the hot water storage tank 24. When the tap water is supplied into the hot water storage tank 24, the temperature of the hot water stored in the hot water storage tank 24 is lowered. Therefore, the heating operation for raising the hot water temperature to the boiling temperature Tb is performed. Normally, the heating operation is performed at night when the electricity bill is cheaper than in the daytime. For example, the heating operation is performed between midnight and 5:00 by a timer operation.

  As shown in FIG. 3, when only the boiling operation in the hot water storage tank 24 is performed, the first three-way valve 7 of the second heat pump circuit 10b is in a state where the port b is closed and the port a and the port c communicate with each other. Has been. The second three-way valve 8 of the second heat pump circuit 10b is in a state where the port d is closed and the port e and the port f are in communication. The third three-way valve 9 of the second heat pump circuit 10b is in a state in which the port m is closed and the port k and the port n communicate with each other. Then, the compressor 1b of the second heat pump circuit 10b is driven.

  In the following description, a case where the boiling temperature Tb, which is the target temperature when boiling water stored in the hot water storage tank 24, is set to 60 ° C. will be described as an example.

  When only the boiling operation is performed, the first heat pump circuit 10a and the heating / warming water circuit 30 are stopped when the heating operation and the boiling operation described with reference to FIG. 2 are performed simultaneously. That is, in the second heat pump circuit 10 b, the refrigerant compressed and discharged by the compressor 1 b flows through the refrigerant pipe 41 from the refrigerant pipe 11 b through the first three-way valve 7, and enters the heat exchange unit 25 of the hot water storage tank 24. Inflow. The refrigerant that has flowed into the heat exchange unit 25 exchanges heat with the water stored in the hot water storage tank 24 and flows out of the heat exchange unit 25. The refrigerant that has flowed out of the heat exchange section 25 flows through the return refrigerant pipe 42 and flows into the refrigerant pipe 11b through the second three-way valve 8.

  The refrigerant flowing into the refrigerant pipe 11b is reduced in pressure when passing through the expansion valve 3b and flows into the heat source side heat exchanger 4b. The refrigerant flowing into the heat source side heat exchanger 4b evaporates by exchanging heat with the air flowing into the heat source side heat exchanger 4b by the rotation of the outdoor fan 6b, and flows out from the heat source side heat exchanger 4b. The refrigerant flowing out from the heat source side heat exchanger 4b flows into the port k of the third three-way valve 9, flows out from the port n into the first bypass pipe 11c, and is sucked into the compressor 1b through the accumulator 5b. It is compressed again.

  Here, in the second heat pump circuit 10b, the temperature of the hot water stored in the hot water storage tank 24, that is, the temperature of the hot water detected by the hot water storage sensor 58 becomes the boiling temperature Tb described above. The rotational speed, the opening degree of the expansion valve 3b, and the rotational speed of the outdoor fan 6b are each controlled.

  As described above, in the heat pump type heating and hot water supply apparatus 100, only the heating operation in the hot water storage tank 24 can be executed alone by operating the second heat pump circuit 10b.

  In addition, if the temperature of the hot water stored in the hot water storage tank 24 becomes the boiling temperature Tb, that is, if the boiling operation is completed, the compressor 1b of the second heat pump circuit 10b is stopped, and the heat pump heating / hot water supply apparatus 100 Stops.

  Next, after the heating operation described above is completed and the heat pump type heating / hot water supply apparatus 100 is stopped using FIGS. 4 and 5, the heat pump type heating / hot water supply apparatus is performed only in the heating operation described with reference to FIG. 1. The case where 100 starts is demonstrated. In the following description, a case where the boiling operation started by the timer operation is completed at 5 am and the heating operation is performed at 7 am will be described as an example.

  When only the second heat pump circuit 10b and only the boiling operation are performed as described with reference to FIG. 3, the boiling rate Tb is high (in this embodiment, the boiling temperature Tb is 60 ° C.). Therefore, the condensation pressure in the heat exchange unit 25 of the hot water storage tank 24 is increased. When the condensing pressure in the heat exchanging unit 25 increases, the refrigerant tends to be biased to the heat source side heat exchanger 4b of the second heat pump circuit 10b.

  In this state, the water in the hot water storage tank 24 rises to the boiling rate Tb at 5 am, the boiling operation is completed, the second heat pump circuit 10b is stopped, and the second heat pump circuit 10b is stopped. A large amount of liquid refrigerant stagnates in the heat source side heat exchanger 4b until 7 am when the time has passed. And if the 2nd heat pump circuit 10b is started in order to start heating operation with the heat pump type heating hot-water supply apparatus 100 at 7:00 am in the state where a large amount of liquid refrigerant has stagnated in the heat source side heat exchanger 4b, the compressor 1b A so-called liquid back in which the liquid refrigerant staying in the heat source side heat exchanger 4b is sucked may occur, and the compressor 1b may be damaged.

  Therefore, the heat pump type heating and hot water supply apparatus 100 of the present invention operates as follows when the heating operation is started after the boiling operation. First, as shown in FIG. 4, the second heat pump circuit 1b is not activated, and the first heat pump circuit 10a and the heating / warming water circuit 30 are activated. At this time, the fourth three-way valve 28 of the heating / warming water circuit 30 is in a state where the port h is closed and the port g and the port j communicate with each other. And the compressor 1b of the 1st heat pump circuit 10a and the circulation pump 22 of the heating hot water circuit 30 are started.

  In the following description, similarly to the case where only the heating operation is performed using FIG. 1, the heating operation set temperature Ti set by the user in the indoor unit 21 is 24 ° C., and this set temperature Ti is set. In order to achieve this, the target hot water temperature Tt, which is the target value of the hot water temperature flowing into the indoor unit 21, will be described as 40 ° C.

  In the heat pump heating / hot water supply circuit 100 shown in FIG. 4, the operation of each component device and the flow of refrigerant and hot water when the first heat pump circuit 10a and the heating / warming water circuit 30 are operating are described with reference to FIG. Since this is the same as the case where the operation and the boiling operation are performed at the same time, detailed description is omitted. Further, in the first heat pump circuit 10a, the temperature of the water flowing out from the water-refrigerant heat exchanger 2a becomes the second predetermined temperature T2 described above, that is, the hot water temperature detected by the first forward temperature sensor 55 is the second temperature. The rotational speed of the compressor 1a, the opening degree of the expansion valve 3a, and the rotational speed of the outdoor fan 6a are each controlled so as to reach the predetermined temperature T2.

  If the temperature of the water flowing out from the water-refrigerant heat exchanger 2a becomes the second predetermined temperature T2 while operating the heat pump heating / hot water supply circuit 100 in the state shown in FIG. 4, as shown in FIG. In addition to the 1 heat pump circuit 10a and the heating / warming water circuit 30, the second heat pump circuit 10b is activated. At this time, the first three-way valve 7 of the second heat pump circuit 10b is in a state in which the port c is closed and the port a and the port b communicate with each other. The second three-way valve 8 of the second heat pump circuit 10b is in a state in which the port f is closed and the port d and the port e communicate with each other. The third three-way valve 9 of the second heat pump circuit 10b is in a state in which the port n is closed and the port k and the port m communicate with each other. The fourth three-way valve 28 of the heating / warming water circuit 30 is in a state in which the port j is closed and the port g and the port h communicate with each other. Then, the compressor 1b of the second heat pump circuit 10b is driven.

  About operation | movement of the heat pump type heating hot-water supply circuit 100 after the 2nd heat pump circuit 10b starts, operation | movement of the 1st heat pump circuit 10a and the heating hot-water supply circuit 30 is operation | movement in the case of performing only the heating operation demonstrated using FIG. Since it is the same, detailed description is abbreviate | omitted. In the second heat pump circuit 10b, the refrigerant compressed and discharged by the compressor 1b flows into the refrigerant side flow path 2ba of the water refrigerant heat exchanger 2b. The refrigerant flowing into the refrigerant side flow path 2ba of the water refrigerant heat exchanger 2b is condensed by exchanging heat with the water flowing through the water side flow path 2bb of the water refrigerant heat exchanger 2b, and flows out of the water refrigerant heat exchanger 2b. To do.

  The refrigerant that has flowed out of the water-refrigerant heat exchanger 2b is decompressed when passing through the expansion valve 3b, and flows into the heat source side heat exchanger 4b. The refrigerant flowing into the heat source side heat exchanger 4b exchanges heat with the air flowing into the heat source side heat exchanger 4b by the rotation of the outdoor fan 6b, and flows out of the heat source side heat exchanger 4b. As described above, in the heat source side heat exchanger 4b, the liquid refrigerant that has slept between the end of the boiling operation (5 am) and the start of the heating operation (7 am) stays. The refrigerant does not evaporate completely in the side heat exchanger 4b, and the refrigerant flows out from the heat source side heat exchanger 4b in a gas-liquid two-phase state.

  The refrigerant that has flowed out of the heat source side heat exchanger 4 b flows into the refrigerant side flow path 23 a of the auxiliary water refrigerant heat exchanger 23 via the third three-way valve 9. The refrigerant that has flowed into the refrigerant-side flow path 23a of the auxiliary water refrigerant heat exchanger 23 evaporates by exchanging heat with the hot water flowing through the water-side flow path 23b of the auxiliary water refrigerant heat exchanger 23, and becomes an auxiliary water refrigerant heat exchanger. 23 flows out. The refrigerant that has flowed out of the auxiliary water refrigerant heat exchanger 23 flows through the refrigerant pipe 11b, is sucked into the compressor 1b through the accumulator 5b, and is compressed again.

  Here, in the first heat pump circuit 10a, the temperature of the water flowing out from the water-refrigerant heat exchanger 2a becomes the first predetermined temperature T1 described above, that is, the hot water temperature detected by the first forward temperature sensor 55 is the first temperature. 1 The rotational speed of the compressor 1a, the opening degree of the expansion valve 3a, and the rotational speed of the outdoor fan 6a are controlled so that the predetermined temperature T1 is obtained. Further, in the second heat pump circuit 10b, the temperature of the water flowing out from the water-refrigerant heat exchanger 2b becomes the above-mentioned second predetermined temperature T2, that is, the hot water temperature detected by the second forward temperature sensor 56 is the second temperature. The rotational speed of the compressor 1b, the opening degree of the expansion valve 3b, and the rotational speed of the outdoor fan 6b are each controlled so as to reach the predetermined temperature T2.

  As described above, in the heat pump heating and hot water supply apparatus 100 of the present embodiment, the second heat pump is used to perform the heating operation after the boiling operation is completed and the second heat pump circuit 10b is stopped in the state shown in FIG. When starting the circuit 1b, after starting the 1st heat pump circuit 10a and the heating hot water circuit 30 shown in FIG. 4 first, and raising the temperature of the water which circulates through the heating hot water circuit 30, as shown in FIG. The second heat pump circuit 10b is activated so that the port k and the port m of the third three-way valve 9 communicate with each other. Thereby, in the auxiliary water refrigerant heat exchanger 23, heat exchange is performed between the refrigerant flowing out from the heat source side heat exchanger 4b and the hot water circulating in the heating hot water circuit 30, so that the heat source side heat exchange is performed after the boiling operation is completed. The refrigerant sleeping in the heat exchanger 4b and not evaporating in the heat source side heat exchanger 4b evaporates in the auxiliary water refrigerant heat exchanger 23 and is sucked into the compressor 1b, so that liquid back to the compressor 1b can be prevented. .

  If the condition described below (sleeping elimination condition) is satisfied, the heat pump type heating / hot water supply apparatus 100 changes from the state shown in FIG. 5 to the state shown in FIG. 1, that is, the ports k and m in the third three-way valve 9. To the auxiliary water refrigerant heat exchanger 23 is switched to a state where the port k and the port n communicate with each other and the auxiliary water refrigerant heat exchanger 23 is bypassed by the first bypass pipe 11c. .

  The stagnation elimination condition is, for example, when the state where the suction superheat degree, which is the superheat degree of the refrigerant on the refrigerant suction side of the compressor 1b, is 5 ° C. or more continues for 5 minutes. That is, the stagnation elimination condition is that all of the liquid refrigerant sleeping in the heat source side heat exchanger 4b flows out of the heat source side heat exchanger 4b, evaporates in the auxiliary water refrigerant heat exchanger 23, and becomes the auxiliary water refrigerant heat exchanger 23. Is a condition indicating that the refrigerant that has completely evaporated in the heat source side heat exchanger 4b is supplied. The suction superheat degree of the compressor 1b is changed from the temperature of the refrigerant flowing out from the auxiliary water refrigerant heat exchanger 23 detected by the auxiliary water heat exchanger temperature sensor 57 to the heat source side exchanger 4b detected by the heat exchanger temperature sensor 53b. It can be obtained by subtracting the temperature of the refrigerant flowing in. Further, the intake superheat degree and the duration thereof may be varied according to the outside air temperature and the temperature of the hot water flowing out from the indoor unit 21.

  As described above, the heat pump type heating and hot water supply apparatus of the present invention, when operating only the hot water supply heat pump circuit, when the hot water supply heat pump circuit is stopped and restarted, Then, heat is exchanged with the refrigerant flowing out from the heat source side heat exchanger in the hot water supply heat pump circuit by the auxiliary water refrigerant heat exchanger. As a result, the liquid refrigerant sleeping in the heat source side heat exchanger is evaporated by exchanging heat with the hot water flowing through the heating hot water circuit before being sucked into the compressor, thereby preventing liquid back to the compressor.

  In the embodiment described above, the heat pump type heating and hot water supply apparatus including two heat pump circuits has been described as an example. However, the heat pump type heating and hot water supply apparatus of the present invention may include three or more heat pump circuits. When three or more heat pump circuits are provided, for example, when the heat load of the heating load is larger than the heat load of the hot water supply load, one heat pump circuit for hot water supply is used, and the heat load of the heating load is the heat load of the hot water supply load. If smaller, the number of hot water supply heat pump circuits may be increased or decreased according to the balance of the heat load between the heating load and the hot water supply load.

DESCRIPTION OF SYMBOLS 1a, 1b Compressor 2a, 2b Water refrigerant | coolant heat exchanger 2aa, 2ba Refrigerant side flow path 2ab, 2bb Water side flow path 7 1st 3 way valve 8 2nd 3 way valve 9 3rd 3 way valve 10a 1st heat pump circuit 10b 2nd Heat pump circuit 11a, 11b Refrigerant pipe 11c First bypass pipe 21 Indoor unit 22 Circulation pump 23 Auxiliary water refrigerant heat exchanger 23a Refrigerant side flow path 23b Water side flow path 24 Hot water storage tank 28 Fourth three-way valve 30 Heating hot water circuit 31 Hot water supply pipe 40 Hot Water Supply Refrigerant Circuit 41 Outgoing Refrigerant Pipe 42 Return Refrigerant Pipe 55 First Outgoing Temperature Sensor 56 Second Outgoing Temperature Sensor 57 Auxiliary Water Heat Exchange Temperature Sensor 100 Heat Pump Heating Water Heater T1 First Predetermined Temperature T2 Second Predetermined Temperature Tb Boiling Temperature Ti Set temperature Tt Target hot water temperature

Claims (2)

A heat pump heating and hot water supply apparatus having a plurality of heat pump circuits, a heating and hot water circuit, and a hot water supply refrigerant circuit,
Each of the plurality of heat pump circuits is configured by sequentially connecting a compressor, a water-refrigerant heat exchanger, a flow rate adjusting unit, and a heat source side heat exchanger through a refrigerant pipe, and at least one of the plurality of heat pump circuits. The heat pump circuit is a heat pump circuit for hot water supply, and the heat pump circuit other than the one constituting the heat pump circuit for hot water supply is a heat pump circuit for heating,
The heating hot water circuit is configured by sequentially connecting a heating load, an auxiliary water refrigerant heat exchanger, a plurality of the water refrigerant heat exchangers, and a circulation pump via a hot water supply pipe,
The hot water supply refrigerant circuit is configured such that the hot water supply load is connected to the hot water supply heat pump circuit by an outgoing refrigerant pipe through which a refrigerant flowing into the hot water supply load flows and a return refrigerant pipe through which a refrigerant flowing out of the hot water supply load flows.
In the hot water supply heat pump circuit, the auxiliary water refrigerant heat exchanger exchanges the heat source side heat exchange so that the refrigerant flowing out of the heat source side heat exchanger flows through the auxiliary water refrigerant heat exchanger and is sucked into the compressor. Connected to the compressor and the compressor by refrigerant piping,
When the hot water supply heat pump circuit is operated to stop the hot water supply heat pump circuit after performing the hot water supply operation by the hot water supply load, and then restart the hot water supply heat pump circuit,
After the heating heat pump circuit is activated first to raise the water circulating in the heating hot water circuit to a predetermined temperature, the hot water supply heat pump circuit is activated, and the heating hot water circuit in the auxiliary water refrigerant heat exchanger Heat exchange between the circulating water and the refrigerant flowing out of the heat source side heat exchanger of the hot water supply heat pump circuit;
A heat pump type heating and hot water supply apparatus characterized by that. The hot water supply heat pump circuit has flow path switching means, and the flow path switching means has at least three connection ports of a first connection port, a second connection port, and a third connection port,
The first connection port of the flow path switching means is connected to the refrigerant outflow side of the heat source side exchanger through a refrigerant pipe, and the second connection port is connected to the refrigerant inflow side of the auxiliary water refrigerant heat exchanger through a refrigerant pipe. And the third connection port is connected to one end of a bypass pipe that bypasses the auxiliary water refrigerant heat exchanger,
The other end of the bypass pipe is connected to a refrigerant pipe connecting the refrigerant outflow side of the auxiliary water refrigerant heat exchanger and the refrigerant suction side of the compressor,
When heat is exchanged between the water circulating in the heating hot water circuit and the refrigerant flowing out of the heat source side heat exchanger of the hot water supply heat pump circuit in the auxiliary water refrigerant heat exchanger, the refrigerant does not flow into the bypass pipe. The flow path switching means is switched to
The heat pump type heating and hot water supply apparatus according to claim 1.

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