JP2012013354A - Heat-pump type hot-water heating device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a heat-pump type hot-water heating device capable of defrosting operation while preventing freezing of a water refrigerant heat exchanger.SOLUTION: The heat-pump type hot-water heating device includes: a refrigerating cycle 6 constituted by sequentially connecting a compressor 1, a four-way valve 30 for switching refrigerant passage, a water refrigerant heat exchanger 2 for performing heat exchange between high temperature refrigerant and water, a pressure reducing device 3, and an outdoor heat exchanger 4 for performing heat exchange between refrigerant and air; a hot water pump 9 for running high-temperature water generated by the water refrigerant heat exchanger 2 to a heating terminal 8; a heater 10 for heating hot water; a bypass circuit 12 for bypassing the heating terminal 8; and a motor-operated valve 13 for switching hot water passage between the bypass circuit 12 and the heating terminal 8. The motor-operated valve 13 is switched to the bypass circuit side 12 during defrosting operation to prevent deterioration of heating feeling felt caused by running low-temperature water to the heating terminal 8 and to prevent freezing of the water refrigerant heat exchanger during defrosting operation.

Description

  The present invention relates to a heat pump hot water heater, and more particularly to defrosting control of an outdoor heat exchanger (evaporator) of the heat pump hot water heater.

  Conventionally, the use of heating devices using combustion fuels such as oil and gas as the heat source has occupied the majority, but in recent years, the heating market using heat pump technology has expanded rapidly. Some conventional air conditioners can also use both cooling and heating by using heat pump technology (see, for example, Patent Document 1).

  FIG. 5 is a configuration diagram of a conventional air conditioner capable of cooling and heating described in Patent Document 1.

  In FIG. 5, a conventional air conditioner has a refrigeration cycle in which a compressor 101, a four-way valve 102, an indoor heat exchanger 103, a pressure reducing device 104, and an outdoor heat exchanger 105 are sequentially connected in an annular manner with refrigerant piping. Have. Each of the indoor heat exchanger 103 and the outdoor heat exchanger 105 includes an indoor fan 106 and an outdoor fan 107 for promoting heat exchange between the air and the refrigerant.

  During the heating operation, the four-way valve 102 is switched as shown in FIG. 5A, the high-temperature refrigerant from the compressor 101 is sent to the indoor heat exchanger 103, and the indoor fan 106 is operated to heat the room. .

  However, when the heating operation is continued in such an air conditioner, the outdoor heat exchanger may be frosted. Therefore, by switching the four-way valve as shown in FIG. 5B, the high-temperature refrigerant discharged from the compressor 101 is directly sent to the outdoor heat exchanger 105, and defrosting is performed with the heat of the refrigerant. At this time, the operation of the indoor fan 106 is stopped so that the room is not cooled.

  In addition, recently, there are problems such as that it is difficult for the feet to be warmed during heating only with a conventional air conditioner, and in order to solve the problem, a hot water heater using a heat pump technology has been developed. The heat pump type hot water heating device is a conventional air conditioner that heats the air and the refrigerant to heat the room, while the water and the refrigerant exchange heat to circulate the hot water in the room. Heating is performed by this.

  FIG. 6 shows a configuration of a conventional heat pump type hot water heater. As shown in FIG. 6, in the conventional heat pump hot water heating apparatus, instead of the indoor heat exchanger 103 shown in FIG. 5, a water-refrigerant heat exchanger 203 that performs heat exchange between water and refrigerant is used. And the hot water pump 205 for sending the warm water produced | generated with the water refrigerant | coolant heat exchanger 203 to heating terminals 204, such as a floor heating panel, is provided.

  In the conventional heat pump type hot water heating apparatus configured as described above, by driving the hot water pump 205, the hot water in the heating terminal 204 can be circulated to heat the room.

JP 2006-336923 A

  However, in the configuration of the conventional heat pump type hot water heating apparatus, the outdoor heat exchanger (evaporator) 105 is frosted when the heating operation is continued, so that the four-way valve 102 is set like the air conditioner. When the defrosting operation of the outdoor heat exchanger 105 is performed after switching, the heat of water passing through the water-refrigerant heat exchanger 203 is taken away by the low-temperature refrigerant, and low-temperature hot water is sent to the heating terminal 204. End up.

  Similarly, when the air conditioner stops the operation of the indoor fan 106 during the defrosting operation, if the operation of the hot water pump 205 is stopped in order not to send the low-temperature water to the heating terminal 204, the water refrigerant There was a problem that water remaining in the heat exchanger 203 would freeze.

  This invention solves the said conventional subject, and it aims at providing the heat pump type hot water heating apparatus which can prevent the fall of the heating feeling at the time of a defrost operation, and the freezing of a water refrigerant | coolant heat exchanger. .

  In order to solve the above-mentioned conventional problems, a heat pump hot water heating apparatus according to the present invention includes a compressor that compresses a refrigerant, a four-way valve that switches a refrigerant flow path, and a water-refrigerant heat exchange in which heat is exchanged between the refrigerant and water. A refrigerating cycle in which an evaporator, a depressurizing device for depressurizing the refrigerant, an evaporator for performing heat exchange between the refrigerant and air are sequentially connected in an annular manner, and hot water generated by heating with the water-refrigerant heat exchanger to the heating terminal A conveying means for sending, a heating means for heating the warm water, a bypass circuit for bypassing the heating terminal, and a switching valve for switching the warm water flow path to the bypass circuit side or the heating terminal side, During the defrosting operation, the switching valve is switched to the bypass circuit side, and it is possible to prevent deterioration of the feeling of heating due to low-temperature hot water flowing to the heating terminal and to heat the hot water means Since comprises, by operating the heating means in response to hot water temperature can be prevented even freezing water refrigerant heat exchanger during the defrosting operation.

  The heat pump hot water heating apparatus of the present invention can perform a defrosting operation without impairing the feeling of heating while preventing the water refrigerant heat exchanger from freezing.

The block diagram of the heat pump type hot water heating apparatus in Embodiment 1 of this invention Flow chart at the time of defrosting operation of the heat pump type hot water heater Configuration diagram of the heat pump type hot water heater (showing the flow of hot water during normal defrosting operation) Configuration diagram of the heat pump type hot water heater (shows the flow of hot water during bypass defrosting operation) (A) Configuration diagram of a conventional air conditioner (showing refrigerant flow during heating operation) (b) Configuration diagram of the air conditioner (showing refrigerant flow during defrosting operation) Configuration diagram of conventional heat pump hot water heater

A first invention includes a compressor that compresses a refrigerant, a four-way valve that switches a refrigerant flow path, a water-refrigerant heat exchanger that exchanges heat between the refrigerant and water, a decompression device that decompresses the refrigerant, and refrigerant and air. A refrigerating cycle in which evaporators that perform heat exchange are sequentially connected in an annular manner, transport means for sending hot water heated and generated in the water-refrigerant heat exchanger to a heating terminal, heating means for heating the hot water, A bypass circuit that bypasses the heating terminal; and a switching valve that switches the hot water flow path to the bypass circuit side or the heating terminal side, and the switching valve is moved to the bypass circuit side during the defrosting operation of the evaporator. In the heat pump type hot water heating device characterized by switching, it is possible to prevent the deterioration of the heating feeling due to the flow of low temperature hot water to the heating terminal, and to operate the heating means according to the hot water temperature, defrosting Driving Freezing of the refrigerant heat exchanger can be prevented.

  2nd invention is provided with the hot water temperature detection means which detects the temperature of the hot water discharged from the said heating means, In the defrost operation of the said evaporator, the hot water temperature detected by the said hot water temperature detection means is more than predetermined temperature In this case, the switching valve is switched to the heating terminal side, and to the bypass side when the temperature is lower than the predetermined temperature, and it is possible to achieve both prevention of a reduction in heating feeling and shortening of the defrosting time. is there.

  3rd invention is equipped with the hot water temperature detection means which detects the temperature of the hot water discharged from the said heating means, In the defrost operation of the said evaporator, based on the hot water temperature detected by the said hot water temperature detection means, It is characterized in that the operation of the heating means is changed, and more efficient defrosting operation can be performed while preventing freezing in the water-refrigerant heat exchanger.

  According to a fourth aspect of the present invention, there is provided a heat pump unit that houses the compressor, the four-way valve, the pressure reducing device, and the evaporator, a water refrigerant heat exchanger, the heating means, the switching valve, and heat that houses the conveying means. The exchange unit is configured as a separate unit, and the heat exchange unit is arranged indoors. The connection between the indoor and the outdoor is made by refrigerant piping, so even in cold districts where the outside air temperature is low The risk of the pipe freezing can be reduced.

  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)
The heat pump type hot water heating apparatus in Embodiment 1 of this invention is demonstrated using FIGS. FIG. 1 is a configuration diagram of a heat pump type hot water heating apparatus in the present embodiment.

  In FIG. 1, the heat pump hot water heating apparatus in the present embodiment exchanges heat between a compressor 1 that compresses refrigerant and discharges high-temperature refrigerant, a four-way valve 30 that switches a refrigerant flow path, and water and high-temperature refrigerant. A water refrigerant heat exchanger 2 that generates high-temperature water, a decompression device 3 that depressurizes the refrigerant, and an outdoor heat exchanger 4 that serves as an evaporator that exchanges heat between the air and the refrigerant are sequentially annularly formed by a refrigerant pipe 5. It has the refrigeration cycle 6 connected to.

  Furthermore, it has the temperature sensor 4a which detects the temperature of the outdoor heat exchanger 4, and the ventilation fan 7 for ventilating to the outdoor heat exchanger 4. FIG. Note that although R410A is used as the refrigerant, other fluorocarbon refrigerants can be used. The compressor 1 is a hermetically sealed type, and a motor (not shown) is disposed on the high pressure side, and a rare earth magnet is used for the motor. Further, by adopting a configuration that does not use an accumulator, it is possible to reduce the size and weight.

  Moreover, the heating terminal 8 (for example, a floor heating panel, a radiation panel, etc.) which heats a living room is provided, the inside of the heating terminal 8 is made to flow the high temperature water produced | generated with the water-refrigerant heat exchanger 2, and the inside of a living room is passed. It is for heating. Therefore, water is configured to circulate between the heating terminal 8 and the water refrigerant heat exchanger 2, and a hot water pump 9 for circulating water is provided.

  Further, in order to prevent the heating capacity of the heat pump from being lowered at the time of low outside air temperature such as in the severe winter season, the hot water temperature is lowered, and the feeling of heating is deteriorated, the heater 10 is provided in the hot water circulation path. On the hot water outlet side, a temperature sensor 10a serving as a hot water temperature detecting means for detecting the hot water temperature is disposed.

  Further, in the present embodiment, a bypass circuit 12 that bypasses the heating terminal 8, that is, bypasses hot water from between the heater 10 and the heating terminal 8 to the suction side of the hot water pump 9, is provided at the inlet of the bypass circuit 12. Is provided with an electric valve 13 for switching the path. During normal heating operation, the motor-operated valve 13 allows hot water to flow toward the heating terminal 8 and prevents hot water from flowing through the bypass circuit 12.

  In the normal heating operation of the heat pump type hot water heating apparatus, the hot water pump 9 is driven to circulate the hot water in the heating terminal 8, and the temperature of the hot water detected by the temperature sensor 10a is controlled by a remote control device or the like (see FIG. The refrigeration cycle is operated until a predetermined temperature higher than the set temperature set in (not shown) is detected. When the temperature detected by the temperature sensor 10a detects a temperature higher than the set temperature by a predetermined temperature, the refrigeration cycle is operated. It comes to stop.

  In addition, the heater 10 is energized and the hot water temperature is reduced only when the heating capacity of the heat pump is reduced and the hot water temperature does not reach the set temperature set by a remote control device (not shown) at a low outside temperature such as in the severe winter season. The temperature is raised to the set temperature, and the energization to the heater 10 is stopped when the set temperature is reached.

  On the other hand, in the operation of the refrigeration cycle, the temperature of the refrigerant discharged from the compressor 1 is detected, and the opening degree of the decompression device 3 is controlled so that the temperature of the discharged refrigerant becomes a predetermined temperature. However, since the temperature of the hot water circulating in the heating terminal 8 must be detected even after the operation of the refrigeration cycle is stopped, the hot water pump 9 is kept driven. The hot water pump 9 may be either an AC pump or a DC pump.

  Moreover, the heat pump type hot water heating apparatus in the present embodiment stores the components other than the water refrigerant heat exchanger 2 among the functional components constituting the refrigeration cycle in the casing of the heat pump unit 11a, and the water refrigerant heat exchanger. 2, The structure which accommodates the hot water pump 9, the heater 10, and the motor operated valve 13 in the housing | casing of the heat exchange unit 11b may be sufficient.

  In this case, the heat pump unit 11a is arranged outdoors, and the heat exchange unit 11b is arranged indoors, so that the indoor and the outdoor are connected by the refrigerant pipe 5. Therefore, even when the outside air temperature is low, such as in winter, the indoor and the outdoor are connected by the refrigerant pipe 5, so that there is an advantage that the risk of freezing is lower than when the water pipe is connected.

  And in the heat pump type hot water heater having a configuration in which the heat pump unit 11a is arranged outdoors and the heat exchange unit 11b is arranged indoors, when the connection between the heat pump unit 11a and the heat exchange unit 11b is released at the time of construction, the heat pump unit The refrigerant must be recovered in 11a. Therefore, as in the present embodiment, in the configuration in which the heat exchange unit 11b is provided indoors, the four-way valve 30 is necessarily required. Moreover, both the heat pump unit 11a and the heat exchange unit 11b have the control devices 14a and 14b, and perform operation instructions to devices provided in each unit.

  Defrosting operation by the heat pump type hot water heater in the present embodiment configured as described above will be described below.

  First, when detecting that the temperature Tg detected by the temperature sensor 4a is lower than the predetermined temperature Ta, the control device 14a determines that the outdoor heat exchanger 4 is frosted and starts the defrosting operation.

  FIG. 2 is a flowchart during the defrosting operation. Hereinafter, the defrosting operation of the present embodiment will be described with reference to FIG.

  When the defrosting operation is started, first, at step 1, it is determined whether or not the tapping temperature To detected by the temperature sensor 10a is higher than the first predetermined temperature Tb. Then, as a result of comparing To with the first predetermined temperature Tb, if the relationship of To ≧ first predetermined temperature Tb is established, the process proceeds to Step 2, and if not, the process proceeds to Step 3.

  Next, in step 2, a normal defrosting operation is performed. In FIG. 3, the hot water circulation channel during the normal defrosting operation is indicated by a thick line. In the normal defrosting operation, the motor-operated valve 13 circulates hot water to the heating terminal 8 as in the case of heating. In the normal defrosting operation, the hot water stored during the heating operation through the water / refrigerant heat exchanger 2 becomes a heat source and heat is supplied to the refrigerant, so that the comfort can be maintained and the normal defrosting operation is performed to shorten the defrosting time. Do.

  In Step 3, a bypass defrosting operation is performed. In FIG. 4, the hot water circulation flow path at the time of the bypass defrosting operation is indicated by a thick line. In the bypass defrosting operation, the motor-operated valve 13 is switched to allow hot water to flow to the bypass circuit 12. Thereby, the low temperature water below predetermined temperature Tb does not flow to heating terminal 8, but comfort can be maintained.

  And if the defrost operation in step 2 or step 3 is started, it will progress to step 4. In step 4, it is determined whether or not the tapping temperature To detected by the temperature sensor 10a is higher than the second predetermined temperature Tc. As a result of comparing the tapping temperature To with the second predetermined temperature Tc, the process proceeds to step 5 if the relation tapping temperature To ≧ second predetermined temperature Tc is established, and proceeds to step 6 if not.

  In step 5, since the hot water temperature To is high to some extent, the heater 10 in the hot water circulation path does not operate.

  In Step 6, it is determined that the remaining water in the water-refrigerant heat exchanger 2 may be frozen because the tapping temperature To is low, the heater 10 in the hot water circulation path is energized, and the tapping temperature. By heating up to the predetermined temperature Td, it is possible to prevent freezing of the water-refrigerant heat exchanger 2 and to shorten the defrosting time.

  Then, after step 5 and step 6, the process proceeds to step 7. In step 7, it is determined whether the temperature Tg detected by the temperature sensor 4a is higher than Ta at which the defrosting operation is started. And when the relationship of outdoor heat exchanger temperature Tg> = Ta is materialized, a defrost operation is complete | finished, the four-way valve 30 is switched, and it returns to heating operation.

  As described above, the heat pump hot water heating apparatus in the present embodiment can maintain the comfort of the heating terminal 8 and can shorten the defrosting time as much as possible.

  In the above embodiment, the heat pump type hot water heating apparatus not provided with the hot water storage tank has been described as an example. However, it goes without saying that the present invention can also be applied to a heat pump type hot water heating apparatus having a hot water storage tank.

  As described above, the heat pump hot water heater according to the present invention can prevent a decrease in heating feeling during defrosting operation and freezing of the water refrigerant heat exchanger, and can be applied to various heat pump hot water heaters. It can be done.

DESCRIPTION OF SYMBOLS 1 Compressor 2 Water refrigerant heat exchanger 3 Pressure reducing device 4 Outdoor heat exchanger (evaporator)
4a Temperature sensor 6 Refrigeration cycle 7 Blower fan 8 Heating terminal 9 Hot water pump (conveying means)
10 Heating heater (heating means)
10a Temperature sensor (Tapping temperature detection means)
11a Heat pump unit 11b Heat exchange unit 12 Bypass circuit 13 Electric valve (switching valve)
30 Four-way valve

Claims (4)

A compressor that compresses the refrigerant, a four-way valve that switches the refrigerant flow path, a water-refrigerant heat exchanger that exchanges heat between the refrigerant and water, a decompression device that depressurizes the refrigerant, and heat exchange between the refrigerant and air Bypassing the heating terminal, a refrigeration cycle in which the evaporators are sequentially connected in an annular manner, a conveying means for sending hot water heated and generated by the water refrigerant heat exchanger to a heating terminal, a heating means for heating the hot water, and the heating terminal A bypass circuit; and a switching valve for switching the hot water flow path to the bypass circuit side or the heating terminal side, wherein the switching valve is switched to the bypass circuit side during the defrosting operation of the evaporator. Heat pump type hot water heater. There is provided a hot water temperature detecting means for detecting the temperature of hot water discharged from the heating means, and in the defrosting operation of the evaporator, when the hot water temperature detected by the hot water temperature detecting means is a predetermined temperature or more, a heating terminal The heat pump hot water heater according to claim 1, wherein the switching valve is switched to a bypass side when the temperature is lower than a predetermined temperature. A hot water temperature detecting means for detecting the temperature of hot water discharged from the heating means is provided, and the operation of the heating means is changed based on the hot water temperature detected by the hot water temperature detecting means in the defrosting operation of the evaporator. The heat pump type hot water heater according to claim 1 or 2, wherein A heat pump unit that houses the compressor, the four-way valve, the pressure reducing device, and the evaporator, and a heat exchange unit that houses the water refrigerant heat exchanger, the heating means, the switching valve, and the conveying means. The heat pump type hot water heating apparatus according to any one of claims 1 to 3, wherein the heat exchange unit is arranged indoors.

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