JP4270216B2 - Supercritical heat pump equipment - Google Patents

Description

  The present invention relates to a supercritical heat pump apparatus that uses CO 2 or the like as a refrigerant, and more specifically, a compressor that compresses the refrigerant to a supercritical pressure, a heating condenser that heats the heating medium, an expansion mechanism, and a sampling that absorbs heat from the atmosphere. The present invention relates to a supercritical heat pump apparatus that includes a refrigerant circuit that circulates refrigerant in order over a heat evaporator, and that includes precooling means for cooling a heat medium to be heated to be passed through the heating condenser.

This type of supercritical heat pump device is unique to supercritical heat pump devices when the heat medium to be heated is at a high temperature by cooling the heat medium to be heated by pre-cooling means prior to heating with the condenser for heating. In this case, the reduction in the coefficient of performance due to the vertical flattening of the refrigeration cycle on the Mollier diagram (that is, the approach of the expansion process part to the compression process part side) has been attempted. As a critical heat pump device, two evaporators are provided in one refrigerant circuit, one of the two evaporators is a heat collecting evaporator that absorbs heat from the atmosphere, and the other evaporator is used as a condenser. There has been proposed a precooling evaporator used as a precooling means for cooling a heating medium to be heated (see Patent Document 1).

JP 2004-3825 A

However, in the conventional supercritical heat pump apparatus as described above , the evaporation temperature of the refrigerant in the heat collecting evaporator, which is the lowest refrigerant temperature in the refrigeration cycle, is determined by the temperature of the air to be absorbed (for example, 0 ° C.) In addition, the refrigerant condensing temperature in the heating condenser, which is the highest refrigerant temperature in the refrigeration cycle, is the target temperature of the heating medium after heating (that is, precooling as a precooling means for the original purpose of heating the heating medium). It is determined by the temperature higher than the temperature of the heating target heating medium before being cooled by the evaporator for heating, for example, 90 ° C., and therefore the evaporation temperature and the maximum refrigerant temperature in the heat collecting evaporator, which are the minimum refrigerant temperatures. The difference from the condensing temperature in the condenser for heating becomes quite large (for example, a temperature difference exceeding 100 ° C ), and the work of the compressor increases for the amount of heat transferred by the heat pump function. Further, it is necessary to heat the heating medium by an amount corresponding to the amount of cooling, and as a result, there is a problem that almost no improvement in the coefficient of performance can be expected.

In view of this situation, the main problem of the present invention is that this kind of cooling and heating mode is adopted to construct a pre-cooling means for cooling the heating medium to be heated prior to heating with the heating condenser. This is to improve the coefficient of performance of the supercritical heat pump device.

[1] A first characteristic configuration of the present invention relates to a supercritical heat pump apparatus,
Two independent refrigerant circuits that circulate the refrigerant in the order of the compressor, the heating condenser, the expansion mechanism, and the heat collecting evaporator are provided side by side, and the refrigerant after passing through the first expansion mechanism in the first refrigerant circuit. As an evaporator to be evaporated, a first heat collecting evaporator that absorbs heat from the atmosphere is provided, and on the other hand, as an evaporator that evaporates the refrigerant after passing through the second expansion mechanism in the second refrigerant circuit, each heating medium to be heated is added to each of the above heating media. A supercritical heat pump apparatus provided with a precooling evaporator for precooling before passing through a heat condenser, wherein the heat medium supplied from an introduction path to the heat pump apparatus is first precooled in the second refrigerant circuit. The preheated heating medium is introduced into the evaporator for preheating, and then the precooled heating medium is passed in series in the order of the first heating condenser of the first refrigerant circuit and the second heating condenser of the second refrigerant circuit. State and first heating condensation of the first refrigerant circuit And in that the second heating condenser of the second refrigerant circuit is provided with switching means for implementing individually and a state in which flow through in parallel.

In the implementation of the first characteristic configuration, the heat medium to be heated which is cooled by the precooling evaporator of the second refrigerant circuit by the switching unit is used as the heating condenser of the first refrigerant circuit and the second refrigerant circuit of the second refrigerant circuit. The operation can be realized by either a series heat medium flow structure for flowing in series with the heating condenser or a parallel heat medium flow structure for flowing in parallel.

That is, according to the first characteristic configuration, in the case of the serial heat medium flow configuration, the main refrigerant circuit (a refrigerant circuit different from the second refrigerant circuit, hereinafter may be referred to as a first refrigerant circuit). When the temperature of the heat medium to be heated before being cooled by the precooling evaporator as the precooling means in the second refrigerant circuit is high, as in the conventional supercritical heat pump device described above, the lowest in the refrigeration cycle evaporation temperature of the refrigerant in the first Tonetsu evaporator as the refrigerant temperature is determined by the temperature of the atmosphere of the heat absorbing interest, also, the condensation temperature of the refrigerant in the first heating condenser the highest coolant temperature during a refrigeration cycle Is determined by the temperature of the heating medium after heating (that is, a temperature higher than the temperature of the heating target heating medium before being cooled by the precooling evaporator). Steaming The difference between the condensation temperature of a temperature and heating condenser is the maximum coolant temperature becomes quite large, yet if you only extra heat amount that has cooled the heat medium in the first refrigerant circuit, the first refrigerant circuit The coefficient of performance of a single unit is about the same as the conventional supercritical heat pump device described above.

However, in the first refrigerant circuit having the serial heating medium flow configuration in which the heating target heating medium cooled by the precooling evaporator is partially heated to a temperature lower than a predetermined heating temperature, the conventional supercritical type described above is used. The coefficient of performance can be increased as compared with the heat pump device.

  On the other hand, for the second refrigerant circuit, when the temperature of the heating medium to be heated before cooling with the precooling evaporator is high, the evaporation temperature of the refrigerant in the precooling evaporator that is the lowest refrigerant temperature in the refrigeration cycle is Since the temperature is determined by the temperature of the high-temperature heating medium, the condensation temperature of the refrigerant in the second heating condenser, which is the highest refrigerant temperature in the refrigeration cycle, is the heat after heating up to a predetermined temperature as in the first refrigerant circuit. Even if it is determined by the temperature of the medium, the difference between the evaporation temperature in the precooling evaporator, which is the minimum refrigerant temperature, and the condensation temperature in the second heating condenser, which is the maximum refrigerant temperature, is the same as that in the first refrigerant circuit. Therefore, the coefficient of performance of the second refrigerant circuit is the same as that of the first refrigerant circuit or the conventional supercritical type described above. Heat pong It can be much higher than the device.

  Therefore, in the case of the heat medium serial flow configuration, the above-described conventional supercritical heat pump device as a whole of the supercritical heat pump device having the first characteristic configuration combining the first refrigerant circuit and the second refrigerant circuit is used. Can have a higher coefficient of performance.

Further, according to the first characteristic configuration, in the case of the parallel heat medium flow configuration, the high temperature before heating by the first heating condenser of the first refrigerant circuit and the second heating condenser of the second refrigerant circuit. By cooling the heating medium to be heated by the pre-cooling means, it is possible to reduce the ratio of the amount of heat due to compression work out of the amount of heat transferred by the heat pump function. Here, if the heating medium is heated by the amount of cooling in the second refrigerant circuit having the precooling evaporator, the coefficient of performance is not improved so much, but only the cooling effect of the heating medium temperature to be heated is received. The coefficient of performance is greatly improved in the first refrigerant circuit. The other variety of the basic effects (e.g., basic improvement of energy consumption efficiency against heat target heating medium is high, reduction in relief (compression ratio of the compressor load) or an apparatus stable operation Naturally, it can be obtained in the same manner as the conventional supercritical heat pump device described above.

That is, according to the first characteristic configuration, the heating condenser is configured in series at a low outside temperature, and in a parallel heating medium configuration in a normal outside temperature. Therefore, it is possible to switch the heat medium flow configuration with respect to the heat medium, thereby increasing the average coefficient of performance of the entire apparatus.

Incidentally, in the case of flow through the series with a second heating condenser of the first heating condenser and the second refrigerant circuit of the first refrigerant circuit to heat the target heat medium, the first heating condensation of the first refrigerant circuit The device is arranged on the upstream side.

In addition, in the case of an equipment configuration in which a heat medium is circulated between a supercritical heat pump device serving as a heat medium heating device and a load device, the heat medium returning from the load device to the supercritical heat pump device (that is, a heat medium to be heated) The first characteristic configuration is particularly suitable when a heat medium is circulated between the supercritical heat pump device and the load device. However, in the implementation of the first characteristic configuration, the heat medium is not necessarily a heat medium circulated between the supercritical heat pump device (specifically, the first heating condenser and the second heating condenser) and the load device. the present invention is not limited, after heating in the first heating condenser and the second heat condenser, again, that without a transient back to their first heating condenser and the second heat condenser Heat medium may be used

[2] The second characteristic configuration of the present invention specifies a more preferable embodiment on the implementation of the first characteristic configuration .
As an evaporator for evaporating the refrigerant after passing through the second expansion mechanism in the second refrigerant circuit, two evaporators, the precooling evaporator and the second heat collecting evaporator that absorbs heat from the atmosphere, are arranged in parallel on the refrigerant circuit. The switching means provided at both the inflow-side refrigerant junction and the outflow-side refrigerant confluence of these two evaporators allows the refrigerant to flow out of the precooling evaporator and the second heat collecting evaporator. This is because the evaporator to be switched is selectively switched.

That is, according to the second characterizing feature, when the temperature of the heating target heat medium is hot, the pre-cooling evaporator of the pre-cooling evaporator and a second Tonetsu evaporator in the second refrigerant circuit by said switching means In the precooling selection state in which the refrigerant flows through the second refrigerant prior to the heating of the heat medium to be heated by the first heating condenser of the first refrigerant circuit and the second heating condenser of the second refrigerant circuit. When the operation mode of cooling by the precooling evaporator of the circuit (that is, the operation mode employed in the first characteristic configuration described above) can be adopted, and thereby the heating target heat medium according to the first characteristic configuration is high temperature The coefficient of performance can be increased.

And also, when the temperature of the heating target heat medium is low does not require cooling at pre-cooling evaporator, the second of the pre-cooling evaporator and a second Tonetsu evaporator in the second refrigerant circuit by said switching means By selecting the heat collection selection state in which the refrigerant flows through the heat collecting evaporator , each heat condensing unit uses the heat pumped from the atmosphere by each heat collecting evaporator in the first refrigerant circuit and the second refrigerant circuit . to be able to heat the heat medium that does not have any extra cooling in vessel, wherein the can reduce the substantial heating load on the heat transfer medium than in the pre-cooling a selected state, thereby, the temperature of the heat target thermal medium Accordingly, in the operation of the apparatus in which the second refrigerant circuit is selectively switched between the precooling selection state and the heat collection selection state, the time-average coefficient of performance as the entire apparatus can be further improved.

  FIG. 1 shows a hot water facility using a supercritical heat pump device as a heat source, 1 is a supercritical heat pump device for CO2 refrigerant, 2A to 2C are hot water storage tanks, and 3 is hot water circulation such as a floor heating panel or a fan coil unit. 4 is a relay heat exchanger, 5 is a hot water circulation type snow melting device, 6 is a bathtub (or hot water pool), and 7 is a hot water tap.

  The heat pump device 1 as a heat source device functions as a hot water heater that heats the hot water W as a heat medium flowing in from the hot water inlet 1a and sends out the heated hot water W from the hot water outlet 1b. In the hot water facility of this example using this, the flow state of the high temperature hot water W sent from the hot water outlet 1b of the heat pump device 1 is changed by switching the flow path by the two upstream and downstream three-way valves Va and Vb. The tank side flow state and the short circuit side flow state are selectively switched.

  That is, in the tank-side flow state, as shown by the one-dot chain line arrow in the figure, the hot water supply water fed from the hot water outlet 1b is branched into the hot water storage tank in which the upstream outward passage 8-the hot water storage tanks 2A to 2C are interposed in series. As shown by the solid line arrow in the drawing, the hot water W sent from the hot water outlet 1b is allowed to pass through the upstream outbound path 8—the short circuit circulation branch. Pass in order of the path 11-the downstream outbound path 10.

The hot water storage tank branch passage 9 is supplied with hot hot water W from the heat pump device 1 fed through the upstream outward passage 8 in the above tank side flow state to the upper portion of the first hot water storage tank 2A. Along with the supply of the high temperature hot water W to the tank 2A, the hot water W sent from the bottom of the first hot water storage tank 2A is supplied to the upper portion of the second hot water storage tank 2B, and similarly, the hot water W to the second hot water storage tank 2B is supplied. hot water W sent from the bottom of the second hot-water tank 2B with the feed supplied to the upper portion of the third hot water tank 2C, and, the third hot water tank 2C with the supply of hot water W of the third water tank 2C Three hot water storage tanks 2 </ b> A to 2 </ b> C are interposed in a serial connection configuration in which hot water W sent from the bottom is sent to the downstream outbound path 10.

That is, by supplying the high-temperature hot water W from the heat pump device 1 in the tank-side flow state, the high-temperature hot water W pushes the residual low-temperature hot water W in the hot water storage tanks 2A to 2C to the downstream outward path 10 by the high-temperature hot water W. W is stored sequentially from the first hot water storage tank 2A side and from the upper side in each of the hot water storage tanks 2A to 2C, and the hot hot water W is stored in a state including partial temperature stratification in each of the hot water storage tanks 2A to 2C. I have to do it.

In the hot water tank branch 9, a hot water supply path 12 is branched from a location between the upstream three-way valve Va and the first hot water storage tank 2 </ b> A, and the hot water supply path 12 is connected to the hot water tap 7. A water supply path 14 with a water supply valve 13 interposed is connected to a location between the third hot water storage tank 2C and the downstream side three-way valve Vb. By supplying fresh water Wc from the water supply path 14 to the bottom of the third hot water storage tank 2C by opening the water supply valve 13, the hot water storage tank is pushed out with the supplied fresh water Wc as shown by the broken arrow in the figure. The stored high temperature hot water W in 2A to 2C is discharged from the hot water tap 7 through the hot water supply path 12 from the upper side of the first hot water storage tank 2A (that is, the high temperature end side without temperature stratification described above). In this hot water supply state, the upstream and downstream three-way valves Va and Vb are in a short circuit side flow state.

  From the downstream side outward path 10, the hot water supply paths 15a and 16a for the warm water circulation type heating device 3 and the relay heat exchanger 4 are branched in parallel, and the downstream side outward path 10 passes through these hot water supply paths 15a and 16a. As hot water W (hot water) is supplied from the heating device 3 and the relay heat exchanger 4 to the heating device 3 and the relay heat exchanger 4, the hot water W (that is, heating) returns from the heating device 3 and the relay heat exchanger 4 through the hot water return paths 15b and 16b. Or hot water that has been consumed by heat exchange and cooled down) is returned to the hot water inlet 1 a of the heat pump device 1 through the common return path 17.

That is, when the hot water W is stored in the hot water storage tanks 2A to 2C (generally at night power hours), in the tank-side flow state (arrows with dashed lines), the heating device 3 and the hot water storage tanks 2A to 2B are used. Short circuit side flow state (solid arrow) in which hot water W as a heat medium is circulated between the relay heat exchanger 4 and the heat pump device 1 while the supply of the high temperature hot water W to the hot water storage tanks 2A to 2C is stopped. Then, hot water W as a heat medium is circulated between the heating device 3 and the relay heat exchanger 4 and the heat pump device 1 through the short circuit circulation branch 11 in a state in which the hot water storage tanks 2A to 2C are bypassed.

  In the relay heat exchanger 4, the water W ′ as an indirect heat medium (that is, water that is not mixed with the hot water W circulated in the heat pump device 1) is heated by heat exchange with the high-temperature hot water W supplied from the downstream outward path 10. Then, the hot water W ′ generated by this heating is circulated to the snow melting device 5 through the circulation paths 18a and 18b, and is circulated to the bathtub 6 (or the hot water pool) through the circulation paths 19a and 19b. That is, the snow melting device 5 prevents the snow accumulation by the retained heat of the hot water W ′ supplied from the relay heat exchanger 4, and the hot water W ′ supplied from the relay heat exchanger 4 in the bathtub 6 (or hot water pool). The stored hot water W ′ is maintained at an appropriate temperature. In the figure, P is a pump.

On the other hand, the heat pump apparatus 1 which is a heat source machine, a first compressor 20 for compressing the refrigerant R to the supercritical pressure, a first heating condenser 21 to heat the hot water W flowing from the hot water inlet 1a, the first a first expansion valve 22 as an expansion mechanism, the air a (typically ambient air) and the first Tonetsu evaporator 23 absorbs heat from the main constituent devices, they first compressor 20- first heating condenser 21 A first refrigerant circuit 24 for circulating the refrigerant R in the order of the first expansion valve 22 and the first heat collecting evaporator 23 is provided.

The second compressor 25 that compresses the refrigerant R ′ to the supercritical pressure, and the second heating condenser that heats the hot water W flowing from the hot water inlet 1a together with the first heating condenser 21 of the first refrigerant circuit 24. 26, a second expansion valve 27 as a second expansion mechanism, and a precooling evaporator 28 as main constituent devices, and independently of the first refrigerant circuit 24, these second compressor 25-second heating condensation The second refrigerant circuit 29 for circulating the refrigerant R ′ in the order of the vessel 26 -the second expansion valve 27 -the precooling evaporator 28 is provided.

Then, the hot water W flowing into the heat pump device 1 from the hot water inlet 1 a is led to the first heating condenser 21 of the first refrigerant circuit 24 and the second heating condenser 26 of the second refrigerant circuit 29 through the introduction path 30. The high-temperature hot water W heated by the first heating condenser 21 and the second heating condenser 26 is sent out from the hot water outlet 1b through the outlet passage 31, and the introduction passage 30 from the hot water inlet 1a is connected to the first passage 30. 2 Precooling evaporator 28 of refrigerant circuit 29 is interposed.

That is, the hot water W to be heated that is led to the first heating condenser 21 of the first refrigerant circuit 24 and the second heating condenser 26 of the second refrigerant circuit 29 through the introduction path 30 is supplied to the first heating condenser. Prior to heating by the condenser 21 and the second heating condenser 26, cooling is performed by the precooling evaporator 28 in the second refrigerant circuit 29 as precooling means.

As an additional equipment, the second refrigerant circuit 29 is equipped with a second heat collecting evaporator 32 that absorbs heat from the atmosphere A (generally outside air) in parallel with the precooling evaporator 28, and the second expansion valve 27. A pre-cooling selection state in which the refrigerant R ′ that has passed through the pre-cooling evaporator 28 is passed through the pre-cooling evaporator 28 and the hot water W to be heated is cooled by the endothermic action of the pre-cooling evaporator 28 (ie, the removal of vaporization heat accompanying the evaporation of the refrigerant); Selection of a heat collection selection state in which the refrigerant R ′ that has passed through the second expansion valve 27 is passed through the second heat collecting evaporator 32 and heat is collected from the atmosphere A by the endothermic action of the second heat collecting evaporator 32. As a switching means for performing a single switching, in order to prevent stagnation due to the stagnation of refrigerant into each evaporator, two refrigerants three-way at both the inflow side refrigerant branch point and the outflow side refrigerant junction point of these two evaporators Valves Vx and Vy are provided.

In addition, in the connection portion of the introduction path 30 and the outlet path 31 with respect to the first heating condenser 21 and the second heating condenser 26, the hot water W to be heated that is guided from the hot water inlet 1 a through the introduction path 30 is a crossover path 33. the closed path between the first heating condenser 21 and the parallel communication flow state to flow through in parallel to the second heating condenser 26, the hot water W over communication flow to be heated which leads through the introduction path 30 from the hot water inlet 1a Two heating medium three-way valves Vc and Vd are provided for switching between a serial flow state in which the first heating condenser 21 and the second heating condenser 26 are passed in series in that order by opening the passage 33. It is.

In other words, in this hot water facility, hot water between the heating device 3 and the relay heat exchanger 4 and the heat pump device 1 through the short circuit circulation branch 11 in a state of bypassing the hot water storage tanks 2A to 2C in which the high temperature hot water W is stored. When the apparatus is operated in the short-circuit side flow state in which W is circulated, the hot water W returning to the heat pump apparatus 1 from the heating apparatus 3 or the relay heat exchanger 4 through the common return path 17 becomes a high temperature (i.e., exceeding Since the hot water W supplied from the critical heat pump device 1 is high temperature (for example, 90 ° C.), the return hot water W is relatively high even if there is a temperature drop due to heat consumption in the heating device 3 or the relay heat exchanger 4. Therefore, as shown by the solid arrows in the figure, the return hot water W is heated to the second refrigerant circuit 29 prior to heating in the first heating condenser 21 and the second heating condenser 26. Steam for pre-cooling While the pre-cooling selection state of cooling in vessel 28, in series in that order with respect to the return hot water W which is cooled in precooler evaporator 28 and the first heating condenser 21 and the second heating condenser 26 Tsuryu In this case, the heated return water W is cooled in the same way, or the cooled back hot water W is passed through the first heating condenser 21 and the second heating condenser 26 in parallel and heated. Te, As a result, the stabilized operation of the heat pump apparatus 1 to reduce the compression ratio to prevent longitudinal flattening of the refrigeration cycle in each of the first refrigerant circuit 24 and the second refrigerant circuit 29, the heat pump device 1 Maintain the coefficient of performance of the entire device as high as possible.

Further, in order to store the hot water W in the hot water storage tanks 2A to 2C , the tank side flow for circulating the hot water W between the heating device 3 and the relay heat exchanger 4 and the heat pump device 1 through the hot water storage tanks 2A to 2C . When the apparatus is operated in the state, the residual low-temperature hot water W in the hot water storage tanks 2A to 2C returns to the heat pump device 1 as returned hot water, so that the refrigerant R 'is passed to the precooling evaporator 28 in the second refrigerant circuit 29. With the flow cut off, the refrigerant R ′ is passed through the second heat collecting evaporator 32, and the second heat collecting evaporator 32 together with the first heat collecting evaporator 23 of the first refrigerant circuit 24 is sent to the atmosphere. The first hot-water condenser 21 is made into a heat collection selection state for causing A to absorb heat, and the return hot water W that has passed through the pre-cooling evaporator 28 without being cooled, as indicated by an alternate long and short dash line in the figure. And the second heating condenser 26 in parallel. It is made into the parallel flow state which is made to flow and it heats, thereby reducing a substantial heating load, shortening the time required for storing hot water W in hot water storage tanks 2A-2C, and making a coefficient of performance higher To do.

In some cases, as indicated by a broken line in the figure, the second water supply passage 34 is connected to the introduction passage 30 and the hot water W from the hot water inlet 1a is supplied to the first heating condenser 21 and the second heating condenser 26. A circulating water heating state in which the water is introduced and heated, and a fresh water heating state in which the fresh fresh water Wc supplied from the second water supply channel 34 is led to the first heating condenser 21 and the second heating condenser 26 to be heated. A water supply three-way valve Ve that performs a single switching operation is provided, so that when the hot water storage tanks 2A to 2C do not store hot hot water W, the water supply valve 13 Instead of opening the valve, switching from the circulating water heating state to the fresh water heating state may be performed to enable the hot water W to be discharged from the hot water tap 7. In this fresh water heating state, as in the tank-side flow state, the second heat collecting evaporator 32 of the second refrigerant circuit 29 is brought into a heat collecting selection state for absorbing heat with respect to the atmosphere A, The return hot water W is made to flow in parallel to the first heating condenser 21 and the second heating condenser 26 so as to be heated.

[Another embodiment]
Next, another embodiment will be listed.

The heat medium heated by the first heating condenser 21 of the first refrigerant circuit 24 and the second heating condenser 26 of the second refrigerant circuit 29 is not limited to the hot water W, but is a heat medium other than hot water for various uses. It may be.

  In the second refrigerant circuit 29, a precooling selection state in which the refrigerant R ′ is passed through the precooling evaporator 28 and the precooling evaporator 28 is cooled with respect to the heating medium W to be heated, and a second heat collecting evaporator. The specific structure of the switching means for selectively switching to the heat collection selection state in which the refrigerant R ′ is caused to flow through 32 and the second heat collecting evaporator 32 absorbs heat with respect to the atmosphere A is described above. It is not restricted to the structure equipped with two refrigerant | coolant three-way valves Vx and Vy as shown in embodiment, A various structure change is possible.

A serial flow state in which the heating medium W to be heated is passed in series to the first heating condenser 21 of the first refrigerant circuit 24 and the second heating condenser 26 of the second refrigerant circuit 29, and in parallel. When switching to the parallel flow state to be passed through the air is possible, the specific structure for the switching is limited to a structure equipped with the two heat medium three-way valves Vc and Vd as shown in the above-described embodiment. Various structural changes are possible.

  The refrigerant R used in the first refrigerant circuit 24 and the refrigerant R ′ used in the second refrigerant circuit 29 are not limited to CO2, but can be compressed to a supercritical pressure and can be expanded and evaporated after the compression. Any refrigerant may be used.

  The refrigerant R used in the first refrigerant circuit 24 and the refrigerant R ′ used in the second refrigerant circuit 29 may be the same refrigerant or different refrigerants.

  Furthermore, the first refrigerant circuit 24 and the second refrigerant circuit 29 are separate heat pump devices regardless of the difference between the respective refrigerants, and may be configured by a combination of two heat pump devices. The device case may be either two cases for separately accommodating the first refrigerant circuit 24 and the second refrigerant circuit 29 or one case for collectively accommodating the refrigerant circuits 24 and 29.

The second expansion mechanism 27 of the first expansion mechanism 22 and the second refrigerant circuit 29 of the first refrigerant circuit 24 is not limited to the expansion valve, it may be a capillary tube.

Circuit diagram showing equipment configuration of hot water equipment and supercritical heat pump equipment

Explanation of symbols

R refrigerant 20 first compressor W heat medium 21 first heating condenser 22 first expansion mechanism A atmosphere 23 first heat collecting evaporator 24 refrigerant circuit (first refrigerant circuit)
R 'refrigerant 25 second compressor 26 second heating condenser 27 second expansion mechanism 28 precooling evaporator, precooling means 29 second refrigerant circuit 32 second heat collecting evaporator Vx, Vy switching means

Claims (2)

Two independent refrigerant circuits that circulate the refrigerant in the order of the compressor, the heating condenser, the expansion mechanism, and the heat collecting evaporator are provided side by side, and the refrigerant after passing through the first expansion mechanism in the first refrigerant circuit. A first heat-collecting evaporator that absorbs heat from the atmosphere is provided as an evaporator to be evaporated. On the other hand, each heating medium to be heated is used as an evaporator that evaporates the refrigerant after passing through the second expansion mechanism in the second refrigerant circuit. A supercritical heat pump apparatus provided with a precooling evaporator for precooling before passing through the condenser for heat, wherein the heat medium supplied from the introduction path to the heat pump apparatus is first used for the precooling of the second refrigerant circuit. A state in which the refrigerant is introduced into the evaporator and precooled, and then the precooled heat medium is passed in series in the order of the first heating condenser of the first refrigerant circuit and the second heating condenser of the second refrigerant circuit; , First condensation for heating of the first refrigerant circuit And supercritical heat pump device is provided with switching means for implementing individually and a state in which flow through the parallel with the second heating condenser of the second refrigerant circuit. As an evaporator for evaporating the refrigerant after passing through the second expansion mechanism in the second refrigerant circuit, two evaporators, the precooling evaporator and the second heat collecting evaporator that absorbs heat from the atmosphere, are arranged in parallel on the refrigerant circuit. The switching means provided at both the inflow-side refrigerant junction and the outflow-side refrigerant confluence of these two evaporators allows the refrigerant to flow out of the precooling evaporator and the second heat collecting evaporator. The supercritical heat pump device according to claim 1, wherein the evaporator to be switched is selectively switched.

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