JP5445170B2 - Heat pump water heater - Google Patents

Description

  The present invention relates to a heat pump water heater using a refrigeration cycle apparatus as a heat source.

  First, the structure of the conventional heat pump water heater will be described. In FIG. 6, 1 is a compressor, 2 is a radiator, 3 is an expansion valve, and 4 is an evaporator, which are configured in an annular shape in this order to form a refrigerant circuit 5. Further, in FIG. 5, 6 is an expansion valve inlet pipe, 7 is an expansion valve outlet pipe, 8 is a water inlet pipe, 9 is a hot water outlet pipe, and 22 is a compressor heat insulating material, and each is arranged as shown in FIG. Typically, it is arranged in a housing.

  The operation of the heat pump water heater configured as described above will be described below.

  The high-pressure refrigerant discharged from the compressor 1 is supplied to the radiator 2, and heat is exchanged with water in the radiator 2 to dissipate heat and then supplied to the expansion valve 3. After being depressurized by the expansion valve 3, it is supplied to the evaporator 4, absorbs heat, and then sucked into the compressor 1. Moreover, the compressor heat insulating material 22 insulates the compressor 1 and maintains the temperature of the refrigerant supplied to the radiator 2 higher.

  On the other hand, the water supplied to the radiator 2 is supplied from the bottom of the hot water storage tank to the radiator 2 through the inlet pipe 8 by the stacking pump, exchanges heat with the refrigerant and becomes hot water, and then passes through the outlet pipe 9 to store the hot water. Reflux to the top of the tank.

  In order to increase the energy efficiency of the heat pump water heater, it is necessary to reduce the amount of heat leakage from a high temperature part such as the compressor 1 so that the compressor 1 is insulated by the compressor heat insulating material 22 (for example, , See Patent Document 1).

JP 2007-192440 A

However, in the heat pump type water heater described in Patent Document 1, although heat leakage from the high-temperature compressor 1 is suppressed, during the defrosting operation in which frost adhering to the evaporator 4 is melted and removed. In particular, no countermeasure is taken against this, although heat transfer from the expansion valve inlet pipe 6 or the expansion valve outlet pipe 7 to the low temperature pipe such as the water inlet pipe 8 or the hot water outlet pipe 9 occurs. Absent.

  When heat leakage occurs from the expansion valve inlet pipe 6 or the expansion valve outlet pipe 7 during the defrosting operation, the heat energy of the refrigerant supplied to the evaporator 4 is reduced, so that the defrosting operation takes longer and the heat pump water heater It had the subject of reducing the energy efficiency of the boiling operation including the defrosting operation.

  The present invention solves the above-described conventional problems, and an object thereof is to provide a heat pump water heater that can suppress heat leakage from the refrigerant pipe during the defrosting operation and prevent prolonged defrosting operation. And

In order to achieve the above object, a heat pump water heater of the present invention includes a compressor, a radiator, a decompression mechanism, a refrigerant circuit formed by sequentially connecting an evaporator that exchanges heat between air and a refrigerant, and the refrigerant circuit. A first refrigerant pipe that supplies a refrigerant from the radiator to the evaporator, a water inlet pipe that supplies water to the radiator, and a hot water that supplies hot water heated from the radiator And a casing that covers the refrigerant circuit, the water inlet pipe, and the hot water outlet pipe , and at least a heating operation for heating water by the radiator and a frost adhering to the evaporator. A heat pump water heater that performs a frost operation, wherein an average distance L1 between the compressor and the first refrigerant pipe and an average distance L2 between the compressor and the water inlet pipe are such that L1> L2. And the compressor and the first refrigerant distribution The first refrigerant pipe is more than the water inlet pipe and the hot water pipe so that the average distance L1 between the compressor and the hot water outlet pipe has a relationship of L1> L3. by arranged in proximity to the housing, disposing a first insulation material between said first refrigerant pipe, the pipe adjacent to the first refrigerant pipe of the entering water pipe or the hot water pipe During the boiling operation , the heat transfer from the high-temperature first refrigerant pipe to the low-temperature inlet pipe or outlet pipe is suppressed during the defrosting operation by increasing the ambient temperature of the inlet pipe and outlet pipe. Thus, it is possible to supply more heat energy to the evaporator to shorten the defrosting operation time, and it is possible to operate the heat pump water heater with high energy efficiency.

  ADVANTAGE OF THE INVENTION According to this invention, the heat pump water heater which can suppress the heat leak from refrigerant | coolant piping at the time of a defrost operation, and can prevent the prolonged defrost operation can be provided.

Horizontal sectional view of the heat pump unit of the heat pump water heater in Embodiment 1 of the present invention Other heat pump unit horizontal direction sectional drawing of the heat pump water heater in Embodiment 1 of this invention Heat pump unit horizontal direction sectional view of the heat pump water heater in Embodiment 2 of the present invention Another heat pump unit horizontal direction sectional view of the heat pump water heater in Embodiment 2 of the present invention. Horizontal sectional view of a heat pump unit of a conventional heat pump water heater Circuit diagram of conventional heat pump water heater

1st invention comprises a refrigerant circuit formed by connecting in order a compressor, a radiator, a decompression mechanism, an evaporator in which air and a refrigerant exchange heat, and a part of the refrigerant circuit to constitute the radiator A first refrigerant pipe for supplying refrigerant to the evaporator, a water inlet pipe for supplying water to the radiator,
A boiling operation for supplying hot water heated from the radiator, and a casing covering the refrigerant circuit, the incoming water pipe, and the outgoing hot water pipe, and heating water at least with the radiator And a defrosting operation for melting the frost adhering to the evaporator, wherein an average distance L1 between the compressor and the first refrigerant pipe, the compressor and the water inlet pipe, And the average distance L2 between the compressor and the first refrigerant pipe and the average distance L3 between the compressor and the outlet pipe are L1. > L3 so that the first refrigerant pipe is disposed closer to the housing than the water inlet pipe and the hot water outlet pipe, and the first refrigerant pipe and the water inlet pipe or the of tapping pipe and the pipe adjacent to the first refrigerant pipe The by disposing a first heat insulating material, at the boiling operation, by increasing the ambient temperature of the entering water pipe and the hot water pipe, in the defrosting operation, the high temperature of the first refrigerant pipe cold It is possible to suppress heat transfer to the incoming or outgoing piping and supply more heat energy to the evaporator to shorten the defrosting operation time, so that the heat pump water heater can be operated with high energy efficiency. .

Further, since the average distance L1 between the compressor and the first refrigerant pipe and the average distance L2 between the compressor and the water inlet pipe have a relationship of L1> L2, leakage from the compressor occurs during the boiling operation. The heat energy is received by the incoming water piping, and the energy efficiency during the boiling operation can be made higher than that of the heat pump water heater in the first to third inventions.

Further, since the average distance L1 between the compressor and the first refrigerant pipe and the average distance L3 between the compressor and the tapping pipe have a relationship of L1> L3, it leaks from the compressor during the boiling operation. It is possible to increase the energy efficiency during the heating operation than the heat pump water heater in the first to fourth inventions by suppressing the heat leakage from the hot water piping to the atmosphere by increasing the atmospheric temperature of the hot water piping by thermal energy. it can.

A second invention is, in particular, Oite to a first aspect of the present invention, the entering-water pipe, characterized in that it is disposed in the vicinity of the compressor than the tapping pipe.

A third invention is, in particular, Oite to the first invention, the tapping pipe, characterized in that than the entering water pipe is disposed in the vicinity of the compressor.

In a fourth aspect of the invention, in particular, in any one of the first to third aspects of the invention, by disposing the first heat insulating material so as to enclose the entire compressor or a part thereof, the high temperature during the defrosting operation. It is possible to reduce the defrosting operation time by suppressing the heat transfer from the first refrigerant pipe to the low temperature inlet pipe or outlet pipe, and the atmosphere of the space surrounded by the first heat insulating material during the boiling operation The temperature can be increased to increase the temperature of the water flowing through the incoming or outgoing hot water piping, and the energy efficiency during the boiling operation can be higher than that of the heat pump water heater in the fourth or fifth invention. it can.

In the fifth invention, in particular, by using the first heat insulating material described in any one of the first to fourth inventions as a vacuum heat insulating material, the heat insulating material can be thinned, and glass wool, pileton or foaming resin can be used. The space around the first refrigerant piping, water inlet piping, and hot water piping is more effective for the arrangement of piping while obtaining the effect of improving the energy efficiency by heat insulation, compared to the case of using heat insulating material with high thermal conductivity of the system. Can be used.

According to a sixth aspect of the present invention , when the compressor is driven, the refrigerant circuit is operated at a supercritical pressure so that the heat leakage is suppressed by heat insulation, and a sufficient temperature difference from the fluid to be heated is obtained even in a high-temperature portion where the refrigerant is not condensed. The heat pump water heater can be operated with high energy efficiency to generate hot water.

In the seventh invention , in particular, by using carbon dioxide as the refrigerant described in the sixth invention , there is no risk of combustion even if the refrigerant leaks, and the heat pump water heater can be operated with peace of mind.

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

(Embodiment 1)
FIG. 1 is a horizontal sectional view of a heat pump unit of a heat pump water heater in the first embodiment of the present invention.

  In FIG. 1, 10 is a first heat insulating material. The expansion valve inlet pipe 6 and the expansion valve outlet pipe 7 are arranged so that the average distance L1 between the compressor 1 and the average distance L2 between the water inlet pipe 8 and the compressor 1 is larger.

  The first heat insulating material 10 is a vacuum heat insulating material and is disposed in the gap between the expansion valve inlet pipe 6 and the water inlet pipe 8 or in the gap between the expansion valve outlet pipe 7 and the water inlet pipe 8. Further, the refrigerant circuit 5 is configured as shown in FIG. 6 similarly to the conventional heat pump water heater, and carbon dioxide circulates as a refrigerant in the refrigerant circuit 5.

  About the heat pump water heater comprised as mentioned above, the operation | movement and an effect | action are demonstrated below.

  When the heat pump water heater is in the defrosting operation state, the first heat insulating material 10 is supplied from the expansion valve inlet pipe 6 (about 25 to 50 ° C.) or the expansion valve outlet pipe 7 (about 5 to 15 ° C.) into the incoming water pipe 8 (about (5-10 ° C.) is suppressed.

  On the other hand, when the heat pump water heater is in the boiling operation state, the first heat insulating material 10 is connected to the expansion valve outlet pipe 7 (about −5 to 7) from the water inlet pipe 8 (about 5 to 10 ° C.) contrary to the defrosting operation. Heat transfer to ° C).

  In addition, the incoming water pipe 8 (about 5 to 10 ° C.) is arranged closer to the compressor 1 (about 10 to 30 ° C.) than the expansion valve inlet pipe 6 and the expansion valve outlet pipe 7, thereby allowing the incoming water pipe. The water flowing through the interior 8 receives the heat energy leaked from the compressor 1 and raises the temperature of the water upstream of the radiator 2.

  Thus, by disposing the first heat insulating material 10 and suppressing heat transfer as described above, during the defrosting operation, heat dissipation from the refrigerant discharged from the compressor 1 is suppressed and evaporation is performed. The heat energy of the refrigerant supplied to the evaporator 4 is maintained at a high level, and the frost attached to the evaporator 4 is quickly melted and removed, and the temperature of the water supplied to the radiator 2 is increased during the boiling operation. Acts as follows.

  As described above, in the present embodiment, the water inlet pipe 8 is disposed closer to the compressor 1 than the expansion valve inlet pipe 6 and the expansion valve outlet pipe 7, and the expansion valve inlet pipe 6 and the expansion valve outlet pipe 7. Frost adhering to the evaporator 4 while maintaining a large thermal energy of the refrigerant supplied to the evaporator 4 during the defrosting operation by disposing the first heat insulating material 10 between the water intake pipe 8 and the water intake pipe 8. Is rapidly melted and removed, and acts to raise the temperature of the water supplied to the radiator 2 during the boiling operation.

As a result, the ratio of the defrosting operation time to the total boiling operation time of the heat pump water heater can be reduced, and the thermal energy required for raising the temperature of the water in the radiator 2 during the heating operation can be reduced. The heat pump water heater can be operated with high energy efficiency.

  In the present embodiment, the water inlet pipe 8 is arranged closer to the compressor 1 than the expansion valve inlet pipe 6 and the expansion valve outlet pipe 7, but the expansion valve inlet pipe 6 and the expansion valve outlet Even if the pipe 7 is arranged nearer to the compressor 1 than the water inlet pipe 8 or in the vicinity thereof, the expansion valve inlet pipe 6 and the expansion valve outlet pipe 7 during the defrosting operation are connected to the water inlet pipe 8. The effect of shortening the defrosting operation time can be obtained by suppressing the heat transfer.

  In the present embodiment, as shown in FIG. 2, the expansion valve inlet pipe 6 and the expansion valve outlet pipe 7 have an average distance L1 between the compressor 1 and an average distance L3 between the tap water pipe 9 and the compressor 1. Also, the hot water piping 9 may be arranged so as to be larger.

  By doing so, during the defrosting operation, heat dissipation from the refrigerant after being discharged from the compressor 1 is suppressed, and the thermal energy of the refrigerant supplied to the evaporator 4 is largely maintained to evaporate. In addition to acting to quickly melt and remove frost adhering to the vessel 4, especially during boiling operation, from a high temperature tap pipe 9 (about 65 to 90 ° C.) to a medium temperature expansion valve inlet pipe 6 (about 5 to 30 ° C.) and the expansion valve outlet pipe 7 (about −5 to 7 ° C.) by suppressing the heat transfer, it acts to suppress the temperature drop of the hot water heated in the radiator 2, and heat pump hot water supply The machine can be operated with high energy efficiency.

  In the present embodiment, the first heat insulating material 10 is a vacuum heat insulating material, but glass wool, pileton or foamed resin may be used. The first heat insulating material 10 may be a heat insulating sound absorbing material integrated with the sound absorbing material.

(Embodiment 2)
FIG. 3 is a horizontal cross-sectional view of the heat pump unit of the heat pump water heater in the second embodiment of the present invention.

  As shown in FIG. 3, the first heat insulating material 10 is disposed so as to surround the surrounding space of the compressor 1, and is not shown in the drawing, but the first heat insulating material 10 is also arranged above the compressor 1 in the vertical direction. It is installed.

  The refrigerant circuit 5 is configured as shown in FIG. 6 similarly to the conventional heat pump water heater and the heat pump water heater described in (Embodiment 1), and carbon dioxide circulates as a refrigerant in the refrigerant circuit 5.

  About the heat pump water heater comprised as mentioned above, the operation | movement and an effect | action are demonstrated below.

  Since the operation when the heat pump water heater is in the defrosting operation state is the same as that of the heat pump water heater described in (Embodiment 1), the details are omitted, but the first heat insulating material 10 includes the expansion valve inlet pipe 6 ( Heat transfer from the expansion valve outlet pipe 7 (about 5 to 15 ° C.) to the water inlet pipe 8 (about 5 to 10 ° C.).

  On the other hand, when the heat pump water heater is in a boiling operation state, the first heat insulating material 10 suppresses heat transfer from the water inlet pipe 8 (about 5 to 20 ° C.) to the expansion valve outlet pipe 7 (about −5 to 7 ° C.). In addition to this, the movement by air convection existing in the space including the compressor surrounded by the first heat insulating material 10 is prevented, and the atmospheric temperature (about 20 to 50 ° C.) of the space is increased. ing.

  In addition to this, the water inlet pipe 8 is closer to the compressor 1 than the expansion valve inlet pipe 6 and the expansion valve outlet pipe 7 (about 20 to 50 ° C.) as in the heat pump water heater described in the first embodiment. Accordingly, the water flowing through the water inlet pipe 8 receives more heat energy leaked from the compressor 1, and the temperature of the water is raised upstream of the radiator 2.

  Thus, by disposing the first heat insulating material 10 and suppressing heat transfer as described above, during the defrosting operation, heat dissipation from the refrigerant discharged from the compressor 1 is suppressed and evaporation is performed. The heat energy of the refrigerant supplied to the evaporator 4 is maintained at a high level, and the frost attached to the evaporator 4 is quickly melted and removed, and the temperature of the water supplied to the radiator 2 is increased during the boiling operation. Acts as follows.

  As described above, in the present embodiment, the water inlet pipe 8 is disposed closer to the compressor 1 than the expansion valve inlet pipe 6 and the expansion valve outlet pipe 7, and the expansion valve inlet pipe 6 and the expansion valve outlet pipe 7 By disposing the first heat insulating material 10 between the inlet water pipe 8 and the defrosting operation, the heat energy of the refrigerant supplied to the evaporator 4 is largely maintained and frost adhering to the evaporator 4 is removed. It melts and removes quickly and acts to raise the temperature of the water supplied to the radiator 2 during the boiling operation.

  As a result, the ratio of the defrosting operation time to the total boiling operation time of the heat pump water heater can be reduced, and the thermal energy required for raising the temperature of the water in the radiator 2 during the heating operation can be reduced. The heat pump water heater can be operated with high energy efficiency.

  In the present embodiment, as shown in FIG. 4, the expansion valve inlet pipe 6 and the expansion valve outlet pipe 7 have an average distance L1 between the compressor 1 and an average distance L3 between the tap water pipe 9 and the compressor 1. Also, the outlet piping 9 may be arranged so as to be larger.

  By doing so, during the defrosting operation, heat dissipation from the refrigerant after being discharged from the compressor 1 is suppressed, and the thermal energy of the refrigerant supplied to the evaporator 4 is largely maintained to evaporate. In addition to acting to quickly melt and remove frost adhering to the vessel 4, especially during boiling operation, from a high temperature tap pipe 9 (about 65 to 90 ° C.) to a medium temperature expansion valve inlet pipe 6 (about 5 to 30 ° C.) and the suppression of heat transfer to the expansion valve outlet pipe 7 (about −5 to 7 ° C.), the ambient temperature of the space surrounded by the first heat insulating material 9 (about 20 to 50 ° C.) By raising the temperature, the heat pump water heater can be operated with high energy efficiency by suppressing the temperature drop of the hot water heated in the radiator 2.

  As described above, the refrigeration cycle apparatus according to the present invention can shorten the defrosting operation time during the defrosting operation, and can operate the heat pump water heater with high energy efficiency. Moreover, it is applicable also to the use of the energy efficiency improvement of the refrigerating cycle apparatus using the heat radiation side, such as a hot water heating apparatus.

DESCRIPTION OF SYMBOLS 1 Compressor 2 Radiator 3 Expansion valve 4 Evaporator 5 Refrigerant circuit 6 Expansion valve inlet piping 7 Evaporator inlet piping 8 Water inlet piping 9 Hot water piping 10 First heat insulating material

Claims (7)

A refrigerant circuit formed by sequentially connecting a compressor, a radiator, a decompression mechanism, an evaporator in which air and refrigerant exchange heat, and
A first refrigerant pipe that constitutes part of the refrigerant circuit and supplies refrigerant from the radiator to the evaporator;
An inlet pipe for supplying water to the radiator;
A hot water supply pipe for supplying hot water heated from the radiator,
A housing that covers the refrigerant circuit, the water inlet piping, and the hot water piping ;
At least a heat pump water heater that performs a boiling operation for heating water with the radiator and a defrosting operation for melting frost adhering to the evaporator,
An average distance L1 between the compressor and the first refrigerant pipe and an average distance L2 between the compressor and the water inlet pipe have a relationship of L1> L2, and the compressor and the first The first refrigerant pipe is connected to the inlet pipe and the outlet pipe so that an average distance L1 to the refrigerant pipe and an average distance L3 between the compressor and the outlet pipe have a relationship of L1> L3. Is also arranged close to the housing,
Wherein the first refrigerant pipe, by disposing the first heat insulating material between the pipe adjacent to the first refrigerant pipe of the entering water pipe or the hot water piping, during the boiling operation, the entering water A heat pump water heater characterized by raising the ambient temperature of the piping and the hot water piping . The heat pump water heater according to claim 1, wherein the water inlet pipe is disposed closer to the compressor than the hot water outlet pipe. The heat pump water heater according to claim 1, wherein the hot water supply pipe is disposed closer to the compressor than the incoming water pipe. The heat pump water heater according to any one of claims 1 to 3, wherein the first heat insulating material surrounds the whole or a part of the compressor. The heat pump water heater according to any one of claims 1 to 4 , wherein the first heat insulating material is a vacuum heat insulating material. It said time compressor drive, the high pressure of the refrigerant circuit heat pump water heater according to any one of claims 1 to 5, characterized in that operating at a supercritical pressure. The heat pump water heater according to claim 6 , wherein carbon dioxide is used as the refrigerant.

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