KR20130102478A - Heat pump type hot water supply apparatus - Google Patents

Abstract

PURPOSE: A water heater in a heat pump type is provided to increase operational efficiency by lowering a temperature of a refrigeration cycle of a refrigerant and a condensing temperature of the refrigerant. CONSTITUTION: A water heater (10) in a heat pump type comprises an evaporator (32), a compressor (34), a first heat exchanger (36), a second heat exchanger (37), an expansion valve (38), a bypass path (50), and a hot water path. The first heat exchanger exchanges heat between a refrigerant and hot water from the compressor. The second heat exchanger exchanges heat between a refrigerant and hot water from the first heat exchanger. The bypass path connects an exit of the first heat exchanger and an entrance of the compressor or the evaporator through the bypass path. The hot water path transfers hot water from the second heat exchanger to the first heat exchanger. [Reference numerals] (12) Gas heat source equipment; (18) Tank; (70) Controller; (AA) Hot-water supply; (BB) Water supply; (CC) Heat pump

Description

Heat pump type hot water supply equipment {HEAT PUMP TYPE HOT WATER SUPPLY APPARATUS}

The technology disclosed here relates to a heat pump type hot water supply device.

Patent Document 1 describes a heat pump type hot water supply device. In the hot water supply device, a compressor having a gas injection port is adopted in a refrigeration cycle of a heat pump. According to this structure, the temperature rise of the water in the discharge gas area | region of the refrigerant discharged | emitted from a compressor can be enlarged, and the condensation temperature is lowered by that much, and high efficiency operation is demonstrated.

Patent Document 1: Japanese Patent Application Laid-Open No. 2008-256281

The technique of patent document 1 requires the special compressor, ie, the compressor which has a gas injection port. Therefore, an increase in manufacturing cost and maintenance cost cannot be avoided. There is a need for a technology that can improve the operating efficiency of a hot water supply device without requiring a special compressor.

The heat pump type hot water supply apparatus according to the present technology includes an evaporator, a compressor, a first heat exchanger, a second heat exchanger, an expansion valve, a bypass path, and a hot water path. The evaporator exchanges heat between the air and the refrigerant. The compressor is connected to the outlet side of the evaporator and compresses the refrigerant from the evaporator. The first heat exchanger is connected to the outlet side of the compressor and performs heat exchange between the refrigerant from the compressor and the hot water. The second heat exchanger is connected to the outlet side of the first heat exchanger, and performs heat exchange between the refrigerant from the first heat exchanger and the hot water. The expansion valve is connected to the outlet side of the second heat exchanger, and the outlet side thereof is connected to the inlet side of the evaporator. The bypass path connects the outlet side of the first heat exchanger to the inlet side of the compressor or the inlet side of the evaporator (that is, the low pressure section of the refrigerant path) via the bypass valve. The hot water path sends hot water to the first heat exchanger and the second heat exchanger in order from the second heat exchanger to the first heat exchanger.

In the above hot water supply device, the high temperature and high pressure refrigerant discharged from the compressor passes through the first heat exchanger and the second heat exchanger in order to exchange heat with the hot water (that is, the hot water is heated while radiating heat). In the first heat exchanger located on the upstream side, the refrigerant is still in the gas phase region, and condensation of the refrigerant begins in the second heat exchanger located on the downstream side. Here, a part of the refrigerant passing through the first heat exchanger is circulated without passing through the second heat exchanger by flowing in the bypass path. In other words, the first heat exchanger in which the refrigerant is in the gas phase region is configured to use more refrigerant than the second heat exchanger in which the refrigerant is condensed. According to such a structure, the temperature rise width of the hot water in a 1st heat exchanger can be enlarged, and even if the temperature rise width of the hot water in a 2nd heat exchanger is made small, the hot water of a hot water supply outlet can be heated to desired tapping temperature. Can be. Therefore, the temperature difference between the refrigerant and the hot water in the second heat exchanger becomes large, and as a result, the condensation temperature of the refrigerant can be lowered, so that the operation efficiency of the hot water supply device can be improved.

BRIEF DESCRIPTION OF THE DRAWINGS The figure which showed typically the structure of the hot water supply apparatus of Example 1
2 is a Moriel diagram showing the refrigeration cycle of the hot water supply device of Example 1
Figure 3 is a diagram showing the state change of the refrigerant and hot water (TH tapping temperature 80 ℃)
4 is a diagram showing a state change of the refrigerant and hot water (TH tapping temperature 60 ℃)
5 is a diagram schematically showing the configuration of a hot water supply device according to a second embodiment;
6 is a Moriel diagram showing the refrigeration cycle of the hot water supply device of Example 2;

In one embodiment of the present technology, it is preferable that the hot water supply device has other hot water storage means. The hot water supply device may be a hot water supply heating device that uses heated hot water for heating as well as hot water supply. It is preferable that the hot water supply device further includes a combustion heat source other than the gas heat source. According to this configuration, when the capacity of the heat pump is significantly lowered, such as when the outside air temperature is very low, hot water supply or heating can be performed using a combustion type heat source.

In one embodiment of the present technology, the refrigerant is preferably a freon-based refrigerant (for example, R410A). However, the coolant is not limited to a freon-based coolant, but may be a coolant other than carbon dioxide.

In one embodiment of the present technology, it is preferable that the bypass path connects the outlet side of the first heat exchanger to the inlet side of the compressor via the bypass valve. In other embodiments, however, it may be desirable for the bypass path to connect the outlet side of the first heat exchanger to the inlet side of the evaporator via a bypass valve. Here, the bypass valve may be an electromagnetic expansion valve or other electric valve, or may be a duty ratio controlled solenoid valve.

Example 1

The hot water supply apparatus 10 of Example 1 is demonstrated with reference to drawings. The hot water supply device 10 is a device for supplying hot water to a hot water supply point such as a faucet (not shown) or a bathtub. As shown in FIG. 1, the hot water supply device 10 includes a hot water storage tank 18 storing hot water, a heat pump 30 circulating heating hot water of the hot water storage tank 18, and a gas heat source device 12 serving as an auxiliary heat source. ). In addition, the hot water supply device 10 may be a hot water supply heating device that uses heat of hot water stored in the water storage tank 18 for heating. In addition, the hot water supply apparatus 10 does not necessarily need to have the water storage tank 18, and may supply the hot water heated by the heat pump 30 directly to a hot water supply location (or a heating location).

A water supply pipe 16 and a hot water supply pipe 14 are connected to the water storage tank 18. The water supply pipe 16 is a pipeline for supplying constant water to the water storage tank 18. The water supply pipe 16 is connected to the bottom of the water storage tank 18. Although not shown, the water supply pipe 16 is provided with various sensors, valves, and the like. The hot water supply pipe 14 is a pipeline for sending hot water from the low temperature tank 18 to the hot water supply point. The tapping pipe 14 is connected to an upper portion of the tapping tank 18. Although not shown in the drawing, the tapping tube 14 is provided with various sensors, valves, and the like.

The gas heat source machine 12 is provided on the path of the tapping pipe 14. The gas heat source device 12 can heat the hot water by burning fuel gas when the temperature of the hot water from the low temperature tank 18 is lower than the required tapping temperature. As a result, the hot water supply device 10 can compensate for the insufficient heat amount by operating the gas heat source device 12 when there is a large or high temperature hot water demand and the hot water amount of the low temperature tank 18 is insufficient for the hot water temperature. . Alternatively, even when the capacity of the heat pump 30 is significantly reduced, such as when the outside air temperature is very low, the required hot water supply can be performed by operating the gas heat source 12.

The heat pump 30 is a heat pump that heats hot water by heating from the atmosphere. The heat pump 30 is connected to the water storage tank 18 via the heating channel 22 and the heating circuit 20. The heating path 22 is a conduit for sending hot water in the water storage tank 18 to the heat pump 30. The heating circuit 20 is a conduit for returning the hot water heated by the heat pump 30 to the water storage tank 18. The heating channel 22 and the heating circuit 20 are connected in series, and constitute a circulation path for circulating hot water between the storage tank 18 and the heat pump 30. A circulation pump 60 is provided in the heating furnace 22. The circulation pump 60 is controlled by the controller 70 of the heat pump 30 described later. Although not shown, various sensors, valves, and the like are provided in the heating path 22 and the heating path 20.

The heat pump 30 includes an evaporator 32, a compressor 34, first and second heat exchangers 36 and 37, and an expansion valve 38. The evaporator 32, the compressor 34, the first and second heat exchangers 36 and 37 and the expansion valve 38 are sequentially connected by the refrigerant paths 42, 44, 46 and 48, and the refrigerant The circulation path which circulates is comprised. Moreover, the heat pump 30 is equipped with the controller 70 which controls the operation | movement of each part.

The evaporator 32 is a heat exchanger that absorbs heat in the air to the refrigerant. The evaporator 32 is blown by the outdoor fan 54. The outdoor fan 54 is driven by the fan motor 56. In the evaporator 32, the mist-like refrigerant passing through the expansion valve 38 absorbs heat in the air and evaporates. As an example, Freon R410A is used as the refrigerant in this embodiment. However, the type of the coolant is not particularly limited, and the coolant may be, for example, carbon dioxide. The fan motor 56 is electrically connected to the controller 70, and its operation, that is, the operation of the outdoor fan 54, is controlled by the controller 70.

The compressor 34 is connected to the outlet side of the evaporator 32 and compresses the refrigerant from the evaporator 32. The refrigerant evaporated in the evaporator 32 is compressed to be adiabatic and brought into a high temperature and high pressure state. The structure and method of the compressor 34 are not particularly limited. The compressor 34 is electrically connected to the controller 70, and the operation of the compressor 34 is controlled by the controller 70.

The first heat exchanger 36 is connected to the outlet side of the compressor 34, and the second heat exchanger 37 is connected to the outlet side of the first heat exchanger 36. The first and second heat exchangers 36 and 37 are heat exchangers that exchange heat between the refrigerant and the hot water. Hot water of the storage tank 18 is sent to the first and second heat exchangers 36 and 37 through the heating channel 22 and the heating channel 20. Here, the hot water is sent from the second heat exchanger 37 in the order of the first heat exchanger 36. Although details will be described later, heat exchange is performed between the coolant in the gas phase region and the hot water in the first heat exchanger 36, and in the second heat exchanger 37, the hot water is heated by dissipating the refrigerant while condensing it. The hot water after the heating is returned to the water storage tank 18 through the heating circuit 20. As a result, hot water is stored in the storage tank 18.

The expansion valve 38 is connected to the outlet side of the second heat exchanger 37. Although the expansion valve 38 of this embodiment is an example, it is an electromagnetic expansion valve which can electrically adjust the opening degree. The expansion valve 38 is electrically connected to the controller 70, and the operation of the expansion valve 38 is controlled by the controller 70. The refrigerant from the second heat exchanger 37 expands rapidly (it becomes a mist phase) by passing through the expansion valve 38. The outlet side of the expansion valve 38 is connected to the inlet side of the evaporator 32, and the refrigerant which has become low pressure (partly misty) is sent to the evaporator 32. In the evaporator 32, as described above, the refrigerant is vaporized by heating from the atmosphere. By the above-mentioned refrigeration cycle, the heat pump 30 can heat the hot water in the boiling water tank 18 using atmospheric heat.

The heat pump 30 further includes a bypass path 50 and a bypass valve 52. The bypass path 50 connects the outlet side of the first heat exchanger 36 to the inlet side of the compressor 34 through the bypass valve 52. As an example, the bypass valve 52 of the present embodiment is a solenoid valve, and the open / close state thereof can be controlled by the controller 70. Instead of the solenoid valve, the bypass valve 52 may adopt an electric valve that can adjust the opening degree by a motor. The specific structure of the bypass valve 52 is not specifically limited. By such a configuration, a part of the refrigerant passing through the first heat exchanger 36 flows into the bypass path 50 and circulates without passing through the second heat exchanger 37. Therefore, in the first heat exchanger 36 in which the refrigerant is in the gas phase region, more refrigerant is used than the second heat exchanger 37 in which the refrigerant is condensed.

The refrigeration cycle described above in Figure 2 is shown by a Moriel diagram. In FIG. 2, P1-P2 represents an endotherm in the evaporator 32. P2-P3 represents an increase in enthalpy due to confluence of the refrigerant from the bypass path 50. P3-P5 represents adiabatic compression in the compressor 34. P5-P6 represents heat dissipation in the first heat exchanger 36. P6-P7 represents heat dissipation in the second heat exchanger 37. P7-P1 represents adiabatic expansion in the expansion valve 38. P6-P4-P3 represents the confluence of the refrigerant from the bypass path 50. In addition, H of a dashed-two dotted line illustrates a refrigerating cycle in the case of not having the bypass path 50. As shown in FIG.

The state change of a refrigerant | coolant and hot water is shown by TH diagram with the desired tapping temperature as 80 degreeC in FIG. As shown in FIG. 2, FIG. 3, the refrigerant | coolant G + g discharged from the compressor 34 exists in a gaseous-phase region, and is about 110 degreeC. The refrigerant is lowered to approximately 60 ° C. by heat exchange with hot water in the first heat exchanger 36. Thereafter, part of the refrigerant G sent to the second heat exchanger 37 dissipates while condensing, and the temperature during that time becomes constant (condensation temperature). Then, when the condensation of the refrigerant G is completed, the temperature of the refrigerant G begins to decrease.

On the other hand, with respect to hot water, when the initial temperature is 10 ° C, the second heat exchanger 37 is heated to 50 ° C. Here, if the amount of refrigerant in the first and second heat exchangers 36 and 37 is the same, if the outlet temperature of the hot water of the second heat exchanger 37 is 50 ° C, the hot water of the first heat exchanger 36 The outlet temperature reaches only about 60 ° C. However, in the present embodiment, the refrigerant G + g used in the first heat exchanger 36 is larger than the refrigerant G used in the second heat exchanger 37. Therefore, the temperature rise width of the hot water in the 1st heat exchanger 36 is large, and the outlet temperature of the hot water of the 1st heat exchanger 36 can reach 80 degreeC of desired tapping temperature. In other words, when the desired tapping temperature (here, 80 ° C.) is obtained, the outlet temperature of the hot water of the second heat exchanger 37 can be relatively low, and the refrigerant and the hot water of the second heat exchanger 37 A sufficient temperature difference can be ensured between them (dashed circle portion J in the drawing). Thereby, the operating efficiency of the hot water supply device 10 can be improved.

The state change of a refrigerant | coolant and hot water is shown by TH diagram with a desired tapping temperature as 60 degreeC in FIG. The lower the desired tapping temperature, the larger the temperature difference is generated between the refrigerant in the second heat exchanger 37 and the hot water. Therefore, when the desired tapping temperature is low (for example, 60 ° C.), even if the temperature of the freezing cycle of the coolant is lowered, a sufficient temperature difference can be ensured between the coolant and the hot water (dashed circle J in the figure). Therefore, by lowering the temperature of the refrigeration cycle of the coolant, the condensation temperature of the coolant can be lowered and the operation efficiency of the hot water supply device 10 can be improved.

As described above, in the hot water supply device 10 according to the present embodiment, the high temperature and high pressure refrigerant discharged from the compressor 34 passes through the first heat exchanger 36 and the second heat exchanger 37 in order to exchange heat with hot water. (Ie, heat the hot water while dissipating it). Part of the refrigerant passing through the first heat exchanger 36 flows into the bypass path 50 and circulates without passing through the second heat exchanger 37. As a result, in the first heat exchanger 36 in which the refrigerant is in the gas phase region, heat exchange is performed by more refrigerant than the second heat exchanger 37 in which the refrigerant is condensed. By such a structure, since the temperature rise width of the warm water in the 1st heat exchanger 36 becomes large, even if the temperature rise width of the warm water in the 2nd heat exchanger 37 is made small by that, it can reach the desired tapping temperature. Can be heated. Alternatively, when the desired tapping temperature is relatively low, the condensation temperature of the refrigerant can be lowered. Thereby, the operating efficiency of the hot water supply device 10 can be improved.

[Example 2]

The hot water supply apparatus 110 of Example 2 is demonstrated with reference to FIG. The hot water supply device 110 according to the present embodiment has a different configuration from the bypass path 50 than the hot water supply device 10 according to the first embodiment shown in FIG. 1. That is, the bypass path 50 of this embodiment connects the outlet side of the first heat exchanger 36 to the inlet side of the evaporator 32 via the bypass valve 52. Even in such a configuration, part of the refrigerant passing through the first heat exchanger 36 flows into the bypass path 50 and circulates without passing through the second heat exchanger 37. As a result, in the first heat exchanger 36 in which the refrigerant is in the gas phase region, heat exchange is performed by more refrigerant than the second heat exchanger 37 in which the refrigerant is condensed. As a result, since the temperature rise of the hot water in the first heat exchanger 36 increases, the hot water can be heated to the desired tapping temperature even if the temperature rise of the hot water in the second heat exchanger 37 is reduced by that amount. have. Alternatively, when the desired tapping temperature is relatively low, the condensation temperature of the refrigerant can be lowered. Thereby, the operating efficiency of the hot water supply device 10 can be improved.

6, the refrigeration cycle of the hot water supply apparatus 110 of Example 2 is shown by a Moriel diagram. In Fig. 6, P1-P2 shows an increase in enthalpy due to the joining of the refrigerant from the bypass path 50. P2-P3 represents the endotherm in the evaporator 32. As shown in FIG. P3-P5 represents adiabatic compression in the compressor 34. P5-P6 represents heat dissipation in the first heat exchanger 36. P6-P7 represents heat dissipation in the second heat exchanger 37. P7-P1 represents adiabatic expansion in the expansion valve 38. P6-P4-P3 represents the confluence of the refrigerant from the bypass path 50. In addition, H of a dashed-two dotted line illustrates a refrigerating cycle in the case of not having the bypass path 50. As shown in FIG.

As mentioned above, although the Example was described in detail, these are only illustrations and do not limit a claim. The technology described in the claims includes various modifications and changes of the specific examples exemplified above. The technical elements described in this specification or the drawings exhibit technical usefulness alone or in various combinations, and are not limited to the combinations described in the claims at the time of filing. In addition, the technology illustrated in the present specification or the drawings can simultaneously achieve a plurality of objects, and has technical usefulness in itself by achieving one of the objects.

10, 110-Hot water supply device 12-Gas heat source
14-Hot water pipe 16-Water pipe
18-Storage Tank 20-Heated Path
22-Heated path 30-Heat pump
32-Evaporator 34-Compressor
36-First Heat Exchanger 37-Second Heat Exchanger
38-Expansion valves 42, 44, 46,48-Refrigerant path
50-Bypass Path 52-Bypass Valve
54-Outdoor Fans 56-Fan Motors
60-Circulating Pump 70-Controller

Claims (4)

An evaporator that exchanges heat between air and refrigerant,
A compressor connected to the outlet side of the evaporator and compressing the refrigerant from the evaporator;
A first heat exchanger connected to the outlet side of the compressor and performing heat exchange between the refrigerant from the compressor and the hot water,
A second heat exchanger connected to an outlet side of the first heat exchanger and performing heat exchange between the refrigerant from the first heat exchanger and the hot water,
An expansion valve connected to an outlet side of the second heat exchanger and connected to an inlet side of the evaporator.
A bypass path connecting the outlet side of the first heat exchanger to the inlet side of the compressor or the inlet side of the evaporator via a bypass valve;
Heat pump type hot water supply device having a hot water path for sending the hot water from the second heat exchanger to the first heat exchanger in order.
The heat exchanger of claim 1, wherein in the first heat exchanger, heat exchange is performed between the refrigerant in the gas phase region and the hot water, and in the second heat exchanger, heat exchange is performed between the refrigerant and the warm water that started condensation. Pump type hot water device.
The heat pump type hot water supply apparatus according to claim 1 or 2, wherein the bypass path is connected to an outlet side of the compressor via the bypass valve of the outlet side of the first heat exchanger.
The heat pump type hot water supply apparatus according to claim 1 or 2, wherein the bypass path is connected to an outlet side of the first heat exchanger through an inlet side of the evaporator through the bypass valve.

Images