JP2007303698A - Hot water supply system - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a hot water supply system capable of raising a temperature of water for hot water supply in a short time, and saving energy in a shop and the like comprising a cold heat equipment such as a refrigeration showcase. <P>SOLUTION: As the water for hot water supply circulated in a hot water supply circuit 40 can exchange heat not only with a first refrigerant circulated in a first refrigerant circuit 10 but also with a second refrigerant circulated in a second refrigerant circuit 30 in this hot water supply system, the temperature of water for hot water supply can be raised in a short time. Further, as the temperature of water for hot water supply can be raised by utilizing the exhaust heat of the second refrigerant circuit 30 comprising the refrigeration showcase 20, and power consumption can be reduced by controlling an operation of an air blower 33 for a second air heat exchanger, COP of the entire shop including the hot water supply system can be improved, and the energy saving in the shop and the like comprising the refrigeration showcase 20 can be achieved. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a hot water supply system used for general household use or business use.

  Conventionally, a hot water supply system including a refrigerant circuit and a hot water supply circuit is known as this type of hot water supply system (see, for example, Patent Document 1). This refrigerant circuit is composed of a compressor, an expansion mechanism, and an air heat exchanger, and the refrigerant is in circulation. The hot water supply circuit includes a hot water storage tank and a pump, and hot water for hot water in the hot water storage tank is circulated by the pump. The hot water supply system configured in this way raises the hot water supply water flowing through the hot water supply circuit to a predetermined temperature by exchanging heat between the refrigerant discharged from the compressor and the hot water supply water flowing through the hot water supply circuit. .

On the other hand, as a cooling system installed in a store such as a convenience store, a system including a refrigerant circuit including a compressor, a condenser, an expansion valve, and an evaporator is known. This cooling system cools refrigeration equipment such as a plurality of refrigerated showcases for storing frozen goods.
JP 2004-144446 A

  However, for example, in winter, when the hot water flowing out of the hot water storage tank of the hot water supply circuit and the refrigerant discharged from the compressor are at low temperatures, the heat between the hot water flowing out of the hot water storage tank and the refrigerant discharged from the compressor is low. Since the exchange rate is low, it takes a long time to raise the temperature of the hot water supply water.

  In addition, in the cooling system installed in the store, exhaust heat is generated from the condenser of the refrigerant circuit, but this heat is released to the outside air without being used at all.

  The present invention has been made in view of the above circumstances, and an object of the present invention is to increase the temperature of hot water supply water in a short time, and for example, a store equipped with a refrigeration equipment such as a refrigerated showcase. It is to provide a hot water supply system that can save energy.

  To achieve the above object, a hot water supply system of the present invention comprises a first compressor, a first expansion mechanism, and a first air heat exchanger, a first refrigerant circuit that circulates a first refrigerant, and a second compressor. , A second expansion mechanism, a second air heat exchanger, and an evaporator for other refrigeration equipment, comprising a second refrigerant circuit for circulating the second refrigerant, a hot water storage tank and a pump, and hot water in the hot water storage tank by the pump A hot water supply circuit for circulating water, a first water heat exchanger for exchanging heat between the first refrigerant discharged from the first compressor and hot water for water flowing through the hot water supply circuit, and a second water discharged from the second compressor. The second water heat exchanger for exchanging heat between the refrigerant and the hot water supply water flowing in the hot water supply circuit, and the air for exchanging heat between the second refrigerant flowing in the second air heat exchanger and the outside air The blower for the second air heat exchanger that blows air, and the supply fed from the second water heat exchanger First temperature detection means for detecting the temperature of the water for use, and blower control means for controlling the operation of the second air heat exchanger blower so that the temperature of the hot water supply water detected by the first temperature detection means becomes a predetermined set temperature. It is the composition provided with.

  According to the hot water supply system of the present invention, heat is exchanged between the first refrigerant discharged from the first compressor and the hot water flowing through the hot water supply circuit in the first water heat exchanger, and the second water heat exchanger is the first in the second water heat exchanger. Heat exchange is performed between the second refrigerant discharged from the two compressors and hot water supply water flowing through the hot water supply circuit. The hot water supply water exchanges heat with the first refrigerant and the second refrigerant, thereby increasing the temperature of the hot water supply water.

  In addition, the refrigerant after heat exchange with the hot water supply water in the second water heat exchanger is exchanged with air in the second air heat exchanger, and then supplied to other refrigeration equipment. At this time, the temperature of the hot water supplied from the second water heat exchanger is detected by the first temperature detection means, and the second air heat exchanger blower is detected by the blower control means based on the detected temperature of the hot water supply water. Is controlled.

  ADVANTAGE OF THE INVENTION According to this invention, heat exchange of the hot water for water supply which distribute | circulates a hot water supply circuit can be performed not only with the 1st refrigerant | coolant which distribute | circulates a 1st refrigerant circuit but with the 2nd refrigerant | coolant which distribute | circulates a 2nd refrigerant circuit. Therefore, the temperature of the hot water supply water can be raised in a short time. In addition, the temperature of the hot water supply water can be increased by utilizing the exhaust heat of the second refrigerant circuit provided with other cooling devices, and the power consumption can be reduced by controlling the operation of the second air heat exchanger blower. Since the energy consumption rate of the entire store including the hot water supply system (hereinafter referred to as COP; COP; Coefficient of Performance) is improved, energy saving can be achieved in stores equipped with other cooling and heating devices. .

  1 and 2 show a hot water supply system according to an embodiment of the present invention. FIG. 1 is a schematic configuration diagram of the hot water supply system, and FIG. 2 is a flowchart showing control of the hot water supply system.

  This hot water supply system constitutes a first refrigerant circuit 10 through which a first refrigerant flows, a plurality of refrigerated showcases 20 for storing refrigerated goods, a refrigeration cycle of the refrigerated showcase 20, and a second refrigerant through which a second refrigerant flows. A refrigerant circuit 30; a hot water supply circuit 40 through which hot water supply water flows; a first water heat exchanger 50 that exchanges heat between the first refrigerant flowing through the first refrigerant circuit 10 and hot water supply water flowing through the hot water supply circuit 40; The second water heat exchanger 60 exchanges heat between the second refrigerant flowing through the second refrigerant circuit 30 and the hot water supply water flowing through the hot water supply circuit 40.

  The first refrigerant circuit 10 includes a first compressor 11, a first expansion valve 12 as an expansion mechanism, a first air heat exchanger 13, and a first water heat exchanger 50, and the first compressor 11 → first water. The first refrigerant can be circulated in the order of the heat exchanger 50 → the first expansion valve 12 → the first air heat exchanger 13 → the first compressor 11. Moreover, the 1st air heat exchanger 13 is arrange | positioned outside, and the 1st air heat exchanger blower 14 which heat-exchanges the 1st refrigerant | coolant in the 1st air heat exchanger 13 and external air is provided. The first refrigerant used in the first refrigerant circuit 10 is a natural refrigerant (for example, carbon dioxide).

  Each refrigerated showcase 20, which is another refrigeration equipment, includes a second expansion valve 21 and an evaporator 22 as an expansion mechanism connected to the second refrigerant circuit 30. The evaporator 22 includes each refrigerated showcase 20. An evaporator blower 23 is provided for heat exchange between the air inside and the second refrigerant in the evaporator 22. Each refrigerated showcase 20 includes a switching valve 24 that switches the flow of the second refrigerant to the second expansion valve 21 and the evaporator 22, and the temperature of each refrigerated showcase 20 is adjusted by switching the switching valve 24. To do.

  The second refrigerant circuit 30 includes a second compressor 31, a second air heat exchanger 32, a second expansion valve 21, an evaporator 22, a switching valve 24, and a second water heat exchanger 60. The second air heat exchanger 32 is provided with a second air heat exchanger blower 33 for exchanging heat between the outside air and the second refrigerant in the second air heat exchanger 32. In the case where the second refrigerant is circulated through the second expansion valve 21 and the evaporator 22, the second refrigerant circuit 30 has a second compressor 31 → a second water heat exchanger 60 → a second air heat exchanger 32 →. The second refrigerant flows in the order of switching valve 24 → second expansion valve 21 → evaporator 22 → second compressor 31. On the other hand, when the switching valve 24 is switched to adjust the temperature of each refrigerated showcase 20, the second compressor 31 → the second water heat exchanger 60 → the second air heat exchanger 32 → the switching valve 24 → the second The second refrigerant flows in the order of the two compressors 31. The second refrigerant used in the second refrigerant circuit 30 is a chlorofluorocarbon refrigerant (for example, R-134a or R-404a).

  The hot water supply circuit 40 includes a hot water storage tank 41, a pump 42, a first water heat exchanger 50, and a second water heat exchanger 60. The hot water storage tank 41 → the pump 42 → the first water heat exchanger 50 → the second water heat. Hot water supply water can be circulated in the order of the exchanger 60 → the hot water storage tank 41. Furthermore, a hot water tank 43 and a hot water supply device 44 are connected to the hot water storage tank 41. This water supply tank 43 is for supplying hot water supply water to the hot water storage tank 41, and the hot water supply device 44 is for discharging the hot water supply water at a set temperature such as a faucet or shower to the outside.

  The first water heat exchanger 50 is shared by the first refrigerant circuit 10 and the hot water supply circuit 40, and exchanges heat between the first refrigerant flowing through the first refrigerant circuit 10 and the hot water supply water flowing through the hot water supply circuit 40. It is.

  The second water heat exchanger 60 is shared by the second refrigerant circuit 30 and the hot water supply circuit 40, and exchanges heat between the second refrigerant flowing through the second refrigerant circuit 30 and the hot water supply water flowing through the hot water supply circuit 40. It is. Further, in the vicinity of the hot water outlet side of the second water heat exchanger 60, there is provided a thermistor 61 as a first temperature detecting means for detecting the temperature T1 of the hot water supplied from the second water heat exchanger 60. .

  Next, the control system configuration of the hot water supply system shown in FIG. 1 will be described. The controller 35 which is a control means for controlling the operation of the second air heat exchanger blower 33 includes a microcomputer (hereinafter referred to as a microcomputer) and various drivers. A detection signal based on the temperature T1 of the hot water flowing through the hot water supply circuit 40 detected by the thermistor 61 is sent to the controller 35, and the temperature T1 of the hot water supplied from the second water heat exchanger 60 in response to this detection signal. The controller 35 controls the energization of the second air heat exchanger blower 33 so that becomes a predetermined set temperature (t1 ≦ T1 ≦ t2).

  Next, the operation of the hot water supply system shown in FIG. 1 will be described with reference to FIG.

  The first refrigerant in the first refrigerant circuit 10 flows in the order of the first compressor 11 → the first water heat exchanger 50 → the first expansion valve 12 → the first air heat exchanger 13 → the first compressor 11 (FIG. (See solid arrow 1).

  The second refrigerant in the second refrigerant circuit 30 is the second compressor 31 → the second water heat exchanger 60 → the second air heat exchanger 32 → the switching valve 24 → the second expansion valve 21 → the evaporator 22 → the second compression. It distributes in the order of the machine 31 (see broken line arrow in FIG. 1). The inside of each refrigerated showcase 20 is cooled by the second refrigerant flowing through the second expansion valve 21 and the evaporator 22. On the other hand, when the switching valve 24 is switched, the second refrigerant flows in the order of the second compressor 31 → the second water heat exchanger 60 → the second air heat exchanger 32 → the switching valve 24 → the second compressor 31. (Refer to broken line arrows in FIG. 1). By switching the switching valve 24, the second refrigerant flows without exchanging heat in each refrigerated showcase 20, and the temperature of each refrigerated showcase 20 is adjusted.

  Hot water for the hot water supply circuit 40 flows in the order of the hot water storage tank 41 → the pump 42 → the first water heat exchanger 50 → the second water heat exchanger 60 → the hot water storage tank 41 (see the white arrow in FIG. 1).

  The first refrigerant, the second refrigerant, and the hot water supply water flow through the circuits 10, 30, and 40, whereby the first refrigerant discharged from the first compressor 11 and the hot water supply circuit 40 flow in the first water heat exchanger 50. The second water heat exchanger 60 exchanges heat between the second refrigerant discharged from the second compressor 31 and the hot water supply water flowing through the hot water supply circuit 40. Thus, the temperature of the hot water supply water rises by exchanging heat between the first and second refrigerants and the hot water supply water.

  At this time, the temperature rises by exchanging heat with the first refrigerant and the second refrigerant, and the temperature T1 of the hot water supplied through the hot water supply circuit 40 sent from the second water heat exchanger 60 is higher than the predetermined set temperature t2. Whether it is low or not is detected by the thermistor 61 (step S1).

  In step S1, when the temperature T1 of the hot water supply water detected by the thermistor 61 is lower than a predetermined set temperature t1, the controller 35 controls the energization of the second air heat exchanger blower 33, and the second air The rotational speed of the heat exchanger blower 33 is decreased (step S2). Since the heat exchange rate between the second refrigerant and the air in the second air heat exchanger 32 is reduced by reducing the rotational speed of the second air heat exchanger blower 33, the temperature T1 of the hot water supply water is a predetermined value. It is prevented from becoming lower than the set temperature t1.

  On the other hand, in step S1, when the temperature T1 of the hot water supply water detected by the thermistor 61 is higher than the predetermined set temperature t1, it is determined whether the temperature T1 of the hot water supply water is higher than the predetermined set temperature t2. (Step S3).

  In step S3, when the temperature T1 of the hot water supply water detected by the thermistor 61 is higher than the predetermined set temperature t2, the controller 35 controls the energization of the second air heat exchanger blower 33, and the second air The number of rotations of the heat exchanger blower 33 is increased (step S4). By increasing the rotation speed of the blower 33 for the second air heat exchanger, the heat exchange rate between the second refrigerant and the air in the second air heat exchanger 32 increases, so that the temperature T1 of the hot water supply water is a predetermined value. It is prevented from becoming higher than the set temperature t2.

  On the other hand, if the temperature T1 of the hot water supply water detected by the thermistor 61 is lower than the predetermined set temperature t2 in step S3, the detection of the temperature T1 of the hot water supply water is continued.

  Thus, according to the hot water supply system of the present embodiment, not only the first refrigerant flowing through the first refrigerant circuit 10 but also the hot water supply circuit 40 flows between the second refrigerant flowing through the second refrigerant circuit 30. Since the heat exchange of the hot water supply water can be performed, the temperature of the hot water supply water can be raised in a short time.

  In addition, the temperature of the hot water supply water can be raised by utilizing the exhaust heat of the second refrigerant circuit 30 provided with the refrigerated showcase 20, and the power consumption is controlled by controlling the operation of the blower 33 for the second air heat exchanger. Therefore, the COP of the entire store including the hot water supply system is improved, and energy saving can be achieved in a store equipped with the refrigerated showcase 20.

  Moreover, since the 1st air heat exchanger 13 has been arrange | positioned outdoors, heat can be taken in into the 1st refrigerant | coolant in the 1st air heat exchanger 13 from external air.

  Further, in the second refrigerant circuit 30, after the heat exchange in the second water heat exchanger 60, further heat exchange is performed in the second air heat exchanger 32, and the second refrigerant having a lower temperature is sent to each refrigerated showcase 20. By doing so, since the second refrigerant having a lower temperature can be circulated through the second expansion valve 21 and the evaporator 22, the inside of each refrigerated showcase 20 can be cooled in a short time.

  3 and 4 show a hot water supply system according to another embodiment of the present invention, FIG. 3 is a schematic configuration diagram of the hot water supply system, and FIG. 4 is a flowchart showing control of the hot water supply system. In addition, the same component as the hot water supply system shown in FIG.1 and FIG.2 is represented with the same code | symbol, and the description is abbreviate | omitted.

  The hot water supply system shown in FIG. 3 has a thermistor 51 as second temperature detecting means for detecting the temperature of hot water supplied from the first water heat exchanger 50 in the vicinity of the hot water outlet side of the first water heat exchanger 50. Is different from the hot water supply system shown in FIG.

  The hot water supply system shown in FIG. 3 includes the controller 36 that controls the energization of the first compressor 11 and the energization of the second air heat exchanger blower 33, and the hot water supply system shown in FIG. Different.

  The thermistor 51 as the second temperature detecting means detects the temperature of the hot water supply water flowing through the hot water supply circuit 40 sent from the first water heat exchanger 50.

  Next, the control system configuration of the hot water supply system shown in FIG. 3 will be described. The controller 36 which is a control means for controlling each operation of the first compressor 11 and the second air heat exchanger blower 33 includes a microcomputer (hereinafter referred to as a microcomputer) and various drivers. A detection signal based on the temperature of the hot water flowing through the hot water supply circuit 40 detected by the thermistor 51 is sent to the controller 36, and the temperature T2 of the hot water supplied from the first water heat exchanger 50 is determined in accordance with this detection signal. The controller 36 controls the energization of the first compressor 11 so that the set temperature (t3 ≦ T2 ≦ t4) is satisfied, and the hot water supply circuit 40 detected by the thermistor 61 as in the hot water supply system shown in FIG. A detection signal based on the temperature of the hot water for water supply is sent to the controller 36, and the temperature T1 of the hot water supplied from the second water heat exchanger 60 in response to this signal is a predetermined set temperature (t1 ≦ T1 ≦ t2). ), The controller 36 controls energization to the second air heat exchanger blower 33.

  Next, the operation of the hot water supply system shown in FIG. 3 will be described with reference to FIG. The circulation of the first refrigerant in the first refrigerant circuit 10, the circulation of the second refrigerant in the second refrigerant circuit 30, and the circulation of hot water in the hot water supply circuit 40 are the same as those in the hot water supply system shown in FIG. The description is omitted.

  The first refrigerant, the second refrigerant, and the hot water supply water flow through the circuits 10, 30, and 40, whereby the first refrigerant discharged from the first compressor 11 and the hot water supply circuit 40 flow in the first water heat exchanger 50. The second water heat exchanger 60 exchanges heat between the second refrigerant discharged from the second compressor 31 and the hot water supply water flowing through the hot water supply circuit 40. Thus, the temperature of the hot water supply water rises by exchanging heat between the first and second refrigerants and the hot water supply water.

  At this time, whether or not the temperature T2 rises by exchanging heat with the first refrigerant, and the temperature T2 of the hot water flowing through the hot water supply circuit 40 sent from the first water heat exchanger 50 is lower than a predetermined set temperature t3. Is detected by the thermistor 51 (step S5).

  In step S5, when the temperature T2 of the hot water supply water detected by the thermistor 51 is lower than the predetermined set temperature t3, the controller 36 controls the energization of the first compressor 11 to turn the first compressor 11 on. The driving state is set (step S6). By bringing the first compressor 11 into a driving state, the high-temperature first refrigerant discharged from the first compressor 11 is supplied to the first water heat exchanger 50, and the first refrigerant in the first water heat exchanger 50 and Since the heat exchange rate with the hot water supply water increases, the temperature T2 of the hot water supply water is prevented from becoming lower than the predetermined set temperature t3.

  On the other hand, in step S5, when the temperature T2 of the hot water supply water detected by the thermistor 51 is higher than the predetermined set temperature t3, it is determined whether the temperature T2 of the hot water supply water is higher than the predetermined set temperature t4. (Step S7).

  In step S7, when the temperature T2 of the hot water supply water detected by the thermistor 51 is higher than the predetermined set temperature t4, the controller 36 controls the energization of the first compressor 11 to control the first compressor 11. A stop state is set (step S8). By stopping the first compressor 11, it is possible to prevent the high-temperature first refrigerant from being discharged from the first compressor 11, and between the first refrigerant and the hot water supply water in the first water heat exchanger 50. Since the heat exchange rate is reduced, the temperature T2 of the hot water supply water is prevented from becoming higher than the predetermined set temperature t4.

  On the other hand, when the temperature T2 of the hot water supply water detected by the thermistor 51 is not higher than the predetermined set temperature t4 in step S7, the detection of the temperature T2 of the hot water supply water is continued.

  Similarly to the hot water supply system shown in FIG. 1, the temperature rises as a result of heat exchange with the first refrigerant and the second refrigerant, and the hot water for the hot water flowing through the hot water supply circuit 40 sent from the second water heat exchanger 60. The temperature T1 is detected by the thermistor 61. The control of the second air heat exchanger blower 33 based on the temperature T1 of the hot water supply water detected by the thermistor 61 is the same as Step S1 to Step S4 shown in FIG.

  According to the hot water supply system of the present embodiment, the power consumption can be further reduced by controlling not only the operation of the second air heat exchanger blower 33 but also the operation of the first compressor 11, including the hot water supply system. The COP of the entire store is further improved, and energy saving can be further achieved in a store equipped with the refrigerated showcase 20. Other operations and effects are the same as those in the first embodiment.

  In each of the above embodiments, the second expansion valve 21 and the evaporator 22 are installed inside the refrigerated showcase 20, but the present invention is not limited to this. For example, the second expansion valve 21 and the evaporator 22 may be installed in a cooling device such as an air conditioner or a refrigerator / refrigerator.

  Moreover, in the said embodiment, although the rotation speed of the air blower 33 for 2nd air heat exchangers was controlled based on the temperature T1 of the hot water supply water detected by the thermistor 61, it is not restricted to this. For example, based on the temperature T1 of the hot water supply water detected by the thermistor 61, control of switching the operation of the second air heat exchanger blower 33 ON / OFF may be performed.

  Furthermore, in the said embodiment, although control which turns ON / OFF operation | movement of the 1st compressor 11 based on temperature T2 of the hot water supply water detected by the thermistor 51 was performed, it is not restricted to this. For example, the rotational speed of the first compressor 11 may be controlled based on the temperature T2 of hot water supply water detected by the thermistor 51.

The schematic block diagram of the hot-water supply system which concerns on one Embodiment of this invention. Flow chart showing control of hot water supply system The schematic block diagram of the hot-water supply system which concerns on other embodiment of this invention. Flow chart showing control of hot water supply system

Explanation of symbols

  DESCRIPTION OF SYMBOLS 10 ... 1st refrigerant circuit, 11 ... 1st compressor, 12 ... 1st expansion valve, 13 ... 1st air heat exchanger, 20 ... Refrigerated showcase, 21 ... 2nd expansion valve, 22 ... Evaporator, 30 ... 2nd refrigerant circuit, 31 ... 2nd compressor, 32 ... 2nd air heat exchanger, 33 ... Blower for 2nd air heat exchanger, 35 ... Controller, 40 ... Hot water supply circuit, 41 ... Hot water storage tank, 42 ... Pump, 50 ... 1st water heat exchanger, 51 ... Thermistor, 60 ... 2nd water heat exchanger.

Claims (3)

A first refrigerant circuit comprising a first compressor, a first expansion mechanism and a first air heat exchanger, and circulating the first refrigerant;
A second refrigerant circuit comprising a second compressor, a second expansion mechanism, a second air heat exchanger, and an evaporator for other refrigeration equipment, and circulating a second refrigerant;
A hot water supply circuit comprising a hot water storage tank and a pump, and circulating hot water in the hot water storage tank by the pump;
A first water heat exchanger that exchanges heat between the first refrigerant discharged from the first compressor and the hot water supply water flowing through the hot water supply circuit;
A second water heat exchanger that exchanges heat between the second refrigerant discharged from the second compressor and the hot water supply water flowing through the hot water supply circuit;
A second air heat exchanger blower that blows air for heat exchange between the second refrigerant circulating in the second air heat exchanger and the outside air;
First temperature detecting means for detecting the temperature of hot water supplied from the second water heat exchanger;
A hot water supply system comprising: blower control means for controlling the operation of the second air heat exchanger blower so that the temperature of the hot water supply water detected by the first temperature detection means becomes a predetermined set temperature. Second temperature detecting means for detecting the temperature of hot water supplied from the first water heat exchanger;
The first compressor control means for controlling the operation of the first compressor so that the temperature of the hot water supply water detected by the second temperature detection means becomes a predetermined set temperature. Hot water system. The hot water supply system according to claim 1 or 2, wherein the first air heat exchanger is disposed outdoors.

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