JP6258804B2 - Combined heat source heat pump device - Google Patents

Description

  The present invention relates to a composite heat source heat pump device, and in particular, when a defrosting operation of an air heat source heat exchanger is started when a second heat pump circuit that uses an air heat source is activated to perform a heating operation, the heating load is large. By changing the defrosting method between when the first heat pump circuit that uses the underground heat source is driven and when the first heat pump circuit that uses the underground heat source is not driven because the heating load is small The present invention relates to a composite heat source heat pump device that reliably performs heating when the heating load is large.

  Recently, “geothermal heat” stored in the earth under the heat of the sun has little change in temperature throughout the year, so geothermal heat pumps that can effectively use this geothermal energy are attracting attention. In particular, geothermal heat pumps have the property that they can be stably heated even in cold regions where the winter is cold.

  Conventionally, a ground having a first compressor, a first heating heat exchanger, a first expansion valve, and a ground heat source heat exchanger in order to support the ground heat heat pump and further improve the heating output by the air heat heat pump. A heat heat pump, a second compressor, a second heating heat exchanger, a second expansion valve, and an air heat heat pump having an air heat source heat exchanger, the first heating heat exchanger and the second heating heat as a condenser An exchanger is connected in series to a heating circulation circuit having a heating circulation pump that circulates the circulating fluid to the heat radiating terminal, and a heat source with high heat collection efficiency is selected according to the outside air temperature, and a geothermal heat pump or air Either one of the heat heat pumps is operated and the heating circulation pump is driven, or both the underground heat pump and the air heat heat pump are operated and applied depending on the size of the heating load. The circulating pump is driven, the heat radiation terminal side of the heating medium heat pump apparatus which performs by heating (circulating fluid) heating operation is supplied to the heat radiating terminal is devised. (For example, patent document 1).

JP 2014-35109 A

  By the way, in such a conventional heat pump cycle device, when the air heat heat pump is activated and heating operation is performed, depending on conditions such as the outside air temperature and the size of the heating load, air heat source heat exchange constituting the air heat heat pump The air heat source heat exchanger may be defrosted, and if the air heat source heat exchanger is frosted, the heat exchange efficiency is lowered, so the air heat source heat exchanger needs to be defrosted.

  As the defrosting operation, the second expansion valve constituting the air heat heat pump is fully opened, and the refrigerant flow direction of the air heat heat pump is reversed from the refrigerant flow direction during the heating operation. The discharged high-temperature refrigerant is directly supplied to the air heat source heat exchanger to melt the frost generated in the air heat source heat exchanger, and the refrigerant flowing out of the air heat source heat exchanger is decompressed by the second expansion valve. Instead, the second expansion valve is passed, the second heating heat exchanger is circulated, and returned to the second compressor again. (Defrosting operation)

  If driving of the heating circulation pump is stopped when performing this defrosting operation, the circulating fluid is not supplied to the heat radiating terminal side, so that no heating is performed and frost generated in the air heat source heat exchanger in the second heating heat exchanger Although the heat exchange is initially performed between the refrigerant whose temperature has been lowered to melt the refrigerant and the circulating fluid staying in the second heating heat exchanger, the temperature of the circulating fluid continues to decrease, Less heat is absorbed from the circulating fluid side to the refrigerant side, and heat used for defrosting the air heat source heat exchanger cannot be taken, resulting in prolonged defrosting operation time. Even when the operation is resumed, since the circulating fluid having a low temperature is supplied to the heat radiation terminal at the beginning of the operation, there is a problem that the feeling of heating is greatly impaired.

  On the other hand, even if the heating circulation pump is continuously driven when the defrosting operation is performed, the refrigerant and the circulating liquid, which have undergone heat exchange to melt the frost generated in the air heat source heat exchanger, become the second heating. Heat is exchanged in the heat exchanger, the circulating fluid is cooled, and the circulating fluid having a low temperature that flows out of the second heating heat exchanger is supplied to the heat radiating terminal. In addition, since the circulating fluid that has flowed out of the heat radiating terminal is not heated, the circulating fluid that flows into the second heating heat exchanger again remains at a low temperature. Therefore, in the second heating heat exchanger, there is also little heat absorbed from the circulating fluid side to the refrigerant side, and heat used for defrosting of the air heat source heat exchanger cannot be taken, and the defrosting operation time is prolonged. It was a thing.

  The present invention has been made in view of such a background, and during the defrosting operation, the heating of the air-conditioned space is favorably continued without greatly reducing the capacity, and the defrosting operation time is not prolonged. It is an object to provide a heat source heat pump device.

In order to solve the above-described problems, the present invention has a configuration in which, in particular, a heating circulation circuit having a heating circulation pump that circulates a circulating liquid in a heat radiating terminal, and a first heating as a condenser disposed in the heating circulation circuit. A heat exchanger, a second heating heat exchanger as a condenser disposed in the heating circulation circuit, a ground heat circulation pump for circulating heat medium and collecting heat from the ground, and this ground heat circulation A ground heat source heat exchanger that heats the first refrigerant circulating in the circuit with a heat medium circulated by a pump, a first compressor that compresses the first refrigerant, and the first compressor that is discharged from the first compressor The first heating heat exchanger for circulating the first refrigerant, and a first expansion valve for depressurizing the first refrigerant flowing out of the first heating heat exchanger, and through the first heating heat exchanger A first heat pump circuit for heating the circulating fluid, and collecting heat from outside air An air heat source heat exchanger for heating the circulating second refrigerant, a second compressor for compressing the second refrigerant, and the second heating heat exchange for circulating the second refrigerant discharged from the second compressor. A second expansion valve that depressurizes the second refrigerant that has flowed out of the second heating heat exchanger, and a switching valve that switches a flow direction of the second refrigerant, and the second heating heat exchanger A second heat pump circuit that heats the circulating fluid via a control device and a control device that controls the operation, wherein the first heating heat exchanger is connected in series to the upstream side of the second heating heat exchanger in the heating circulation circuit. disposed in the in the composite source heat pump apparatus which performs heating operation for heating the circulating liquid by driving the heating circulation pump actuates the second heat pump circuit, said control device, said second heat pump circuit air The defrosting operation to melt the frost on the Minamotonetsu exchanger, wherein when driving the first heat pump circuit, the flow path in the switching valve performs in the first defrosting operation Ru changeover example, the first heat pump circuit when not driving the the flow path by the switching valve is obtained to perform the second defrosting operation to raise the discharge temperature of the second compressor not a switching example.

Further in claim 2, wherein the first defrosting operation, so as to reduce the rotational speed of the heating circulation pump, the second defrost operation is obtained by the heating circulation pump to be driven stops .

  According to this invention, before the defrosting of the second heat pump circuit is started, it is confirmed whether or not the first heat pump circuit for geothermal heat is being driven, and when the first heat pump circuit is being driven, the second heating heat exchanger The second compression that does not stop the heating in the second heating heat exchanger while the switching valve for stopping the heating performs the first defrosting operation for switching the flow path of the second refrigerant and the first heat pump circuit is stopped. By performing the second defrosting operation for raising the discharge temperature of the machine, the defrosting of the second heat pump circuit can be completed reliably or in a short time without impairing the feeling of heating in the heating circuit. Is.

  In the second aspect of the present invention, the rotation speed of the heating circulation pump is reduced during the first defrosting operation, and the heating circulation pump is stopped during the second defrosting operation. When two heat pump circuits are driven, heating is prioritized without stopping heating, and when only one of the second heat pump circuits is driven with a small heating load, the reliability of defrosting and heating By selecting the defrost considering the quick start-up, the defrost of the second heat pump circuit can be completed reliably or in a short time without impairing the feeling of heating in the heating circuit.

The external appearance block diagram which shows the main units of the composite heat source heat pump apparatus which concerns on embodiment of this invention. The block diagram which shows the whole structure of the composite heat source heat pump apparatus which concerns on embodiment of this invention. The route diagram which shows the defrost operation which concerns on embodiment of this invention. The flowchart of the principal part which concerns on embodiment of this invention.

The configuration of the composite heat source heat pump apparatus 1 according to the embodiment of the present invention will be described in detail with reference to FIGS. 1 and 2 as appropriate.
As shown in FIG. 1, the composite heat source heat pump device 1 includes a ground heat pump unit 4 including a first heat pump circuit 40 (see FIG. 2) and an air heat heat pump unit including a second heat pump circuit 50 (see FIG. 2). 5. The composite heat source heat pump device 1 includes a heating circulation circuit 30 as a load-side circulation circuit that circulates a circulation liquid L (for example, hot water or antifreeze liquid) as a heat medium in the heat radiating terminal 36, and a ground heat as a heat source-side circulation circuit. It has a circulation circuit 20, a control device 6 (61, 62, 63) as control means for controlling the operation of the composite heat source heat pump device 1, and a remote controller 60 that sends a signal to the control device 6.

  As shown in FIG. 2, the composite heat source heat pump apparatus 1 according to the present embodiment uses a ground heat source to heat the circulating liquid L on the heat radiating terminal 36 side, and the first heating heat exchanger 41 of the first heat pump circuit 40. And a combined heat source heat pump in which a second heating heat exchanger 51 of a second heat pump circuit 50 that heats the circulating liquid L on the heat radiation terminal 36 side using an air heat source is connected in series to the heating circulation circuit 30 The first heating heat exchanger 41 is disposed upstream of the second heating heat exchanger 51 with respect to the flow of the circulating liquid L circulating in the heating circulation circuit 30. The composite heat source heat pump device 1 can function as a heating device and a cooling device, but in the following embodiments, components and operations when mainly used as a heating device will be described.

  The first heat pump circuit 40 circulates the first variable-capacity compressor 43 that compresses the first refrigerant C1 and the high-temperature first refrigerant C1 discharged from the first compressor 43, and the high-temperature first refrigerant C1. And a first heating heat exchanger 41 as a first condenser that performs heat exchange between the circulating fluid L flowing in the heating circulation circuit 30 and a first refrigerant C1 that flows out of the first heating heat exchanger 41 is depressurized. As a first expansion valve 44 that performs heat exchange between the first expansion valve 44 serving as a decompression unit, the decompressed low-temperature first refrigerant C1 from the first expansion valve 44, and the heat medium H1 that flows through the underground heat circulation circuit 20. The underground heat source heat exchanger 45 and a first refrigerant pipe 42 that connects these in an annular shape are configured. The first heat pump circuit 40 circulates the first refrigerant C1 and heats the circulating liquid L flowing through the heating circulation circuit 30 via the first heating heat exchanger 41.

  In the underground heat pump unit 4 shown in FIG. 2, reference numeral 42a is a first refrigerant discharge temperature sensor that detects the temperature of the first refrigerant C1 discharged from the first compressor 43, and reference numeral 42b is a first refrigerant discharge temperature sensor. 1st refrigerant | coolant temperature sensor provided in the 1st refrigerant | coolant piping 42 from the 1 expansion valve 44 to the underground heat source heat exchanger 45, ie, the 1st refrigerant | coolant piping 42 of a low voltage | pressure side, and detects the temperature of the 1st refrigerant | coolant C1 of a low voltage | pressure side. It is.

  The second heat pump circuit 50 circulates the variable-capacity second compressor 53 that compresses the second refrigerant C2 and the high-temperature second refrigerant C2 discharged from the second compressor 53, and this high-temperature second refrigerant C2 And the second heating heat exchanger 51 as a second condenser for exchanging heat with the circulating liquid L flowing through the heating circulation circuit 30, and the second refrigerant C2 flowing out from the second heating heat exchanger 51 is depressurized. The heat of the second expansion valve 54 serving as a decompression means and the low-temperature second refrigerant C2 decompressed from the second expansion valve 54 circulates and the air sent by the operation of the low-temperature second refrigerant C2 and the blower fan 56. An air heat source heat exchanger 55 serving as a second evaporator that performs exchange and a second refrigerant pipe 52 that connects these in an annular shape are configured. The second heat pump circuit 50 circulates the second refrigerant C2 and heats the circulating liquid L flowing through the heating circulation circuit 30 via the second heating heat exchanger 51.

The second refrigerant pipe 52 is provided with a four-way valve 58 as a switching valve for switching the flow direction of the second refrigerant C2 in the second heat pump circuit 50, and the four-way valve 58 is discharged from the second compressor 53. The second refrigerant C2 is circulated in the order of the second heating heat exchanger 51, the second expansion valve 54, and the air heat source heat exchanger 55 to form a flow path that returns to the second compressor 53 (state during heating operation) ) And the second refrigerant C2 discharged from the second compressor 53 are circulated in the order of the air heat source heat exchanger 55, the second expansion valve 54, and the second heating heat exchanger 51, and returned to the second compressor 53. It can be switched to a state in which a flow path is formed.
In the present embodiment, when the air heat source heat exchanger 55 becomes low temperature and frosts, the second refrigerant C2 discharged from the second compressor 53 is directed toward the air heat source heat exchanger 55 as shown in FIG. The four-way valve 58 is switched so as to flow, and frost generated in the air heat source heat exchanger 55 is melted by the high-temperature second refrigerant C2 from the second compressor 53, and the second refrigerant C2 The defrosting which switches a flow path is called 1st defrosting operation.

  In the air heat heat pump unit 5 shown in FIG. 2, reference numeral 52a is a second refrigerant discharge temperature sensor that detects the temperature of the second refrigerant C2 discharged from the second compressor 53, and reference numeral 52b is a second refrigerant discharge temperature sensor. The second refrigerant temperature sensor is provided in the second refrigerant pipe 52 from the expansion valve 54 to the air heat source heat exchanger 55, that is, the second refrigerant pipe 52 on the low pressure side, and detects the temperature of the second refrigerant C2 on the low pressure side. Reference numeral 57 denotes an outside air temperature sensor for detecting the outside air temperature.

  In addition to the first defrosting operation, the second refrigerant discharge is performed so as to increase the temperature of the second refrigerant C2 discharged from the second compressor 53 instead of switching the flow path by the four-way valve 58. The rotational speed of the second compressor 53 is controlled so that the temperature detected by the temperature sensor 52a is set in advance to reach the target temperature, whereby the second refrigerant C2 having a temperature higher than normal is exchanged with the second heating heat. And the second expansion valve 54 in the fully opened state, and the second refrigerant C2 in the warm state enters the air heat source heat exchanger 55 to melt the frost adhering thereto, and has a second defrosting operation in which this circulation is sequentially repeated. Is.

  In addition, as a refrigerant | coolant of the 1st heat pump circuit 40 and the 2nd heat pump circuit 50, arbitrary refrigerant | coolants, such as HFC refrigerant | coolants, such as R410A and R32, and a carbon dioxide refrigerant | coolant, can be used.

  The 1st heating heat exchanger 41, the underground heat source heat exchanger 45, and the 2nd heating heat exchanger 51 are comprised by the plate type heat exchanger, for example. In this plate heat exchanger, a plurality of heat transfer plates are stacked, and a refrigerant flow path for circulating a refrigerant and a fluid flow path for circulating a fluid as a heat medium are alternately formed with each heat transfer plate as a boundary. ing.

  The underground heat circulation circuit 20 includes a underground heat source heat exchanger 45 and a plurality of U-shaped tubes embedded in the ground as a heat source for heating the first refrigerant C1 flowing through the underground heat source heat exchanger 45. The underground heat exchanger 23 and the underground heat pipe 21 connecting these in an annular shape are configured. In addition, the underground heat pipe 21 has a variable rotation speed (the number of rotations per unit time) for circulating an antifreeze liquid in which ethylene glycol, propylene glycol or the like is added as a heat medium H1 to the underground heat circulation circuit 20. A pump 22 is provided. In addition, the code | symbol 24 in FIG. 2 is the underground system turn which adjusts the pressure of the underground heat circulation circuit 20 by storing the heat medium H1.

  Here, in the underground heat circulation circuit 20, when performing the heating operation, the underground heat exchanger 23 collects the underground heat from the ground, and the heat medium H <b> 1 with the heat is the underground heat circulation pump 22. Is supplied to the underground heat source heat exchanger 45. In the underground heat source heat exchanger 45, the first refrigerant C1 that flows through the refrigerant flow path of the underground heat source heat exchanger 45 and the heat medium H1 that flows through the fluid flow path of the underground heat source heat exchanger 45 are Heat exchange is performed by flowing in the opposite direction, the underground heat collected by the underground heat exchanger 23 is pumped to the first refrigerant C1 side, the first refrigerant C1 is heated, and the underground heat source heat exchanger 45 functions as an evaporator.

  The heating circuit 30 includes a first heating heat exchanger 41 as a first condenser, a second heating heat exchanger 51 as a second condenser, a floor heating panel and a panel convector for heating the air-conditioned space, etc. The heat radiating terminal 36 as a load terminal and a heating pipe 31 that connects these in a circular shape in order from the upstream side are provided. The heating pipe 31 is provided with a heating circulation pump 32 that circulates the circulating liquid L in the heating circulation circuit 30. Each of the heating pipes 31 branched for each heat radiation terminal 36 is opened and closed to open the heat radiation terminal 36. Thermally operated valves 33 are provided for controlling the supply of the circulating fluid L to each. In addition, although the two heat radiating terminals 36 are provided in FIG. 2, one may be sufficient and three or more may be sufficient, and quantity and a specification are not specifically limited.

  Thus, in the heating circulation circuit 30, the first heating heat exchanger 41 as the first condenser and the second heating heat exchanger 51 as the second condenser are connected in series, and the heating circulation circuit 30 is The circulating liquid L to be circulated is configured to be supplied to the heat radiating terminal 36 through the second heating heat exchanger 51 after flowing through the first heating heat exchanger 41.

  In the heating circulation circuit 30 shown in FIG. 2, reference numeral 34 denotes a return hot water temperature sensor that detects the temperature of the circulating fluid L that is provided in the heating pipe 31 and flows into the first heating heat exchanger 41 from the heat radiating terminal 36. Reference numeral 35 denotes a heating system that stores the circulating fluid L and adjusts the pressure of the heating circulation circuit 30.

  The control device 6 includes a geothermal heat pump control device 61 that controls the operation of the underground heat circulation circuit 20, the first heat pump circuit 40, and the heating circulation circuit 30, and an air heat heat pump that controls the operation of the second heat pump circuit 50. A control device 62 and a defrosting operation control device 63 as defrosting operation control means for controlling the defrosting operation are provided. The control device 6 includes a storage unit that stores various data and programs, and a control unit that performs calculation / control processing. Each temperature sensor such as the outside air temperature sensor 57 and the temperature sensors 42a and 42b, and the remote control 60 The operation of the composite heat source heat pump device 1 can be controlled in response to the signal from.

  During the heating operation, the control device 6 sets the detection value of the return hot water temperature sensor 34 that detects the temperature of the circulating fluid L immediately upstream of the first heating heat exchanger 41 based on the set temperature of the remote controller 60. In the heating operation by the operation of the first heat pump circuit 40, the rotation speed of the first compressor 43 is controlled so as to reach the target hot water temperature, and in the heating operation by the operation of the second heat pump circuit 50, the second compressor. 53, the rotational speed of the first compressor 43 and the second compressor 53 is controlled when both the first heat pump circuit 40 and the second heat pump circuit 50 are operating. That is, the control device 6 is installed in the heating circulation circuit 30 immediately upstream of the first heating heat exchanger 41, and the detection value of one return hot water temperature sensor 34 that detects the temperature of the circulating fluid L that has flowed out from the heat radiation terminal 36. To determine the overall heating load, and control the operation of either the first heat pump circuit 40 or the second heat pump circuit 50, or both the first heat pump circuit 40 and the second heat pump circuit 50 according to this. It is configured as follows.

  The defrosting operation control device 63 determines whether the outside air temperature detected by the outside air temperature sensor 57 of the second heat pump circuit 50 has reached a preset defrosting start temperature, or the outside air temperature detected by the outside air temperature sensor 57. And whether or not the refrigerant temperature detected by the second refrigerant temperature sensor 52b has reached a preset defrosting start temperature, that is, whether or not a predetermined defrosting start condition is satisfied, is removed. If it is determined that the frost start condition is satisfied, it is next checked whether or not the first heat pump circuit 40 is driven, and when the first heat pump circuit 40 is driven, the above-described refrigerant flow path is switched. While performing 1 defrost operation, reducing the rotation speed of the heating circulation pump 32 from 3500 rpm at the time of heating operation to 2500 rpm at the time of this 1st defrost operation, performing defrost reliably, 1st, 1st 2 When both the pump circuits 40 and 50 are driven and the heating load is large, the second heating heat exchanger 51 is not cooled strongly even if the second heating heat exchanger 51 enters the cooling state. In order to obtain heat, the rotational speed of the heating circulation pump 32 is limited.

  Further, it is confirmed whether or not the first heat pump circuit 40 is driven. When the first heat pump circuit 40 is not driven, the refrigerant flow is not switched and the discharge of the second compressor 53 is performed. While performing the 2nd defrost operation which raises temperature, the drive of the heating circulation pump 32 is stopped, and since the heating load is small only by the drive of the 2nd heat pump circuit 50, heating at the heat radiating terminal 36 is stopped for a short time. In the meantime, the defrost is surely defrosted and the frost adhering to the air heat source heat exchanger 55 is melted, and since the flow path is not switched, the rapid start-up of the heating operation from the defrost operation is used. Thus, the feeling of heating is not impaired by returning to the immediate heating operation.

Next, the operation of the composite heat source heat pump apparatus 1 shown in FIGS. 1 and 2 will be described.
When the remote control 60 gives an instruction to heat the air-conditioned space by the heat radiating terminal 36, the control device 6 uses the ground heat source and the first heat pump circuit 40 and the air heat source based on the outside air temperature detected by the outside air temperature sensor 57. Of the second heat pump circuits 50 using the above, the one having the better heat collection efficiency is selected and operated as the heat source.

  For example, when the outside air temperature is not so low (for example, 5 ° C. or more) as in spring or autumn, and the heating load is small, the control device 6 operates only the second heat pump circuit 50 using the air heat source. Let In this case, the control device 6 starts driving the second compressor 53, the second expansion valve 54, the blower fan 56, and the heating circulation pump 32, and the heating operation is started. When the heating operation is started, the second heating heat exchanger 51 exchanges heat between the circulating liquid L circulated by the heating circulation pump 32 and the high-temperature and high-pressure second refrigerant C2 discharged from the second compressor 53, The heated circulating liquid L is supplied to the heat radiating terminal 36 to heat the air-conditioned space, and in the air heat source heat exchanger 55, the air sent by driving the blower fan 56 and the low-temperature and low-pressure discharged from the second expansion valve 54. The second refrigerant C2 is heat-exchanged, and the second refrigerant C2 is heated and evaporated by air heat. In this case, the circulating liquid L circulating in the heating circuit 30 also passes through the first heating heat exchanger 41. At this time, since the first heat pump circuit 40 is not operated, the first heating heat is not supplied. The exchanger 41 passes without being heated.

  On the other hand, when the outside air temperature is low as in winter (for example, 5 ° C. or less), the control device 6 operates only the first heat pump circuit 40 that uses the underground heat source. In this case, the control device 6 starts driving the first compressor 43, the first expansion valve 44, the underground heat circulation pump 22, and the heating circulation pump 32, and the heating operation is started. When the heating operation is started, the first heating heat exchanger 41 exchanges heat between the circulating liquid L circulated by the heating circulation pump 32 and the high-temperature and high-pressure first refrigerant C1 discharged from the first compressor 43, The heated circulating liquid L is supplied to the heat radiating terminal 36 to heat the air-conditioned space, and in the underground heat source heat exchanger 45, it is circulated by the underground heat circulation pump 22 and underground through the underground heat exchanger 23. The heat medium H1 that has collected heat and the low-temperature and low-pressure first refrigerant C1 discharged from the first expansion valve 44 exchange heat, and the first refrigerant C1 is heated and evaporated by underground heat. In this case, the circulating fluid L circulating in the heating circulation circuit 30 also passes through the second heating heat exchanger 51. At this time, since the second heat pump circuit 50 is not operated, the second heating heat The exchanger 51 passes through without being heated.

  Further, when the heating operation is started up or when either the first heat pump circuit 40 or the second heat pump circuit 50 is operated to perform the heating operation, the outside air temperature further decreases, and the heating load is increased. Thus, when a desired heating output cannot be obtained by only one operation, the control device 6 performs the heating operation in which both the first heat pump circuit 40 and the second heat pump circuit 50 are operated. In the case of the heating operation in which both the first heat pump circuit 40 and the second heat pump circuit 50 are operated as an example, the control device 6 includes the first compressor 43, the first expansion valve 44, the underground heat circulation pump 22, the first The 2 compressor 53, the 2nd expansion valve 54, the ventilation fan 56, and the heating circulation pump 32 are driven, and heating operation is performed. During the heating operation, in the first heating heat exchanger 41, the circulating fluid L circulated by the heating circulation pump 32 and the high-temperature and high-pressure first refrigerant C1 discharged from the first compressor 43 flow oppositely to generate heat. Exchange is performed and the circulating liquid L is heated, and in the second heating heat exchanger 51, the circulating liquid L circulated by the heating circulation pump 32 and the high-temperature and high-pressure second refrigerant discharged from the second compressor 53. C2 flows oppositely, heat exchange is performed, and the circulating liquid L is heated. As described above, the circulating liquid L circulating in the heating circuit 30 is heated by the first heating heat exchanger 41 and then further heated by the second heating heat exchanger 51 to be supplied to the heat radiating terminal 36. When the circulation liquid 36 is circulated, the heat of the circulating liquid L is radiated to the air-conditioned space, whereby the air-conditioned space is heated.

  Next, as a characteristic operation, a defrosting operation is performed to melt the frost generated in the air heat source heat exchanger 55 when the second heat pump circuit 50 used by the air heat source is operated to perform the heating operation. The operation of the composite heat source heat pump apparatus 1 will be described with reference to the flowchart of FIG.

  The heating operation of operating the second heat pump circuit 50 and driving the heating circulation pump 32 to heat the circulating fluid L in the second heating heat exchanger 51 and supplying the heated circulating fluid L to the heat radiating terminal 36. If the defrosting operation control device 63 determines that the defrosting start condition is satisfied from the outside air temperature detected by the outside air temperature sensor 57 during the process (step S1), the process proceeds to step S2 with YES. It is confirmed whether or not the 1 heat pump circuit 40 is driven. When the first heat pump circuit 40 is driven, the first defrosting operation of switching the refrigerant flow path with the four-way valve 58 is performed in step S3 with YES. At the same time, the rotational speed of the heating circulation pump 32 is reduced from 3500 rpm during the heating operation to 2500 rpm during the first defrosting operation, so that the defrosting is reliably performed, and the first and second heat pump circuits. In order to prevent the second heating heat exchanger 51 from being cooled strongly even when 0 and 50 are both driven and the heating load is large, the heat from the first heating heat exchanger 41 is reduced. In order to obtain this, the number of rotations of the heating circulation pump 32 is limited.

  Next, when the first heat pump circuit 40 is not driven in step S2, the process proceeds to step S4 with NO, and the refrigerant flow path is not switched by the four-way valve 58, and the second discharge that raises the discharge temperature of the second compressor 53 is performed. While performing the frost operation, stopping the heating circulation pump 32 and driving only the second heat pump circuit 50, the heating load is small, so it is determined that there is no problem even if heating at the heat radiation terminal 36 is stopped for a short time, In the meantime, the defrost is surely defrosted and the frost adhering to the air heat source heat exchanger 55 is melted, and since the flow path is not switched, the rapid start of the heating operation from the defrosting operation is used, and the heating operation is immediately performed. By returning, the feeling of heating is not impaired.

  Then, when performing the defrosting operation, the defrosting operation control device 63 finishes the predetermined defrosting from the temperature of the second refrigerant C2 that has passed through the air heat source heat exchanger 55 detected by the second refrigerant temperature sensor 52b. It is determined that the condition is satisfied (step S5), and the process proceeds to step 6 with YES to end the defrosting operation and return to the state before the defrosting. As described above, the second heat pump circuit 50 It rises quickly and quickly returns to heating operation.

DESCRIPTION OF SYMBOLS 1 Composite heat source heat pump apparatus 6 Control apparatus 22 Geothermal circulation pump 30 Heating circulation circuit 32 Heating circulation pump 36 Heat radiation terminal 40 1st heat pump circuit 41 1st heating heat exchanger 43 1st compressor 44 1st expansion valve 45 Underground Heat source heat exchanger 50 Second heat pump circuit 51 Second heating heat exchanger 53 Second compressor 54 Second expansion valve 55 Air heat source heat exchanger 58 Four-way valve (switching valve)
61 Geothermal heat pump control device 62 Air heat heat pump control device 63 Defrosting operation control device C1 First refrigerant C2 Second refrigerant L Circulating fluid

Claims (2)

A heating circulation circuit having a heating circulation pump that circulates a circulating liquid in a heat radiating terminal, a first heating heat exchanger as a condenser disposed in the heating circulation circuit, and a condenser disposed in the heating circulation circuit As a second heating heat exchanger, a ground heat circulation pump that circulates the heat medium and collects heat from the ground, and a first refrigerant that circulates in the circuit with the heat medium circulated by the ground heat circulation pump A ground heat source heat exchanger for heating the first refrigerant, a first compressor for compressing the first refrigerant, the first heating heat exchanger for circulating the first refrigerant discharged from the first compressor, A first expansion valve for depressurizing the first refrigerant flowing out from the first heating heat exchanger, and a first heat pump circuit for heating the circulating fluid via the first heating heat exchanger; An air source heat exchanger that heats and heats the second refrigerant circulating in the circuit; A second compressor that compresses the second refrigerant; the second heating heat exchanger that causes the second refrigerant discharged from the second compressor to flow; and the second that flows out of the second heating heat exchanger. A second heat pump circuit that has a second expansion valve that depressurizes the refrigerant and a switching valve that switches a flow direction of the second refrigerant, and that heats the circulating fluid via the second heating heat exchanger; The first heating heat exchanger is arranged in series upstream of the second heating heat exchanger in the heating circulation circuit, operates the second heat pump circuit and the heating in the composite heat source heat pump apparatus which performs heating operation for heating the circulating liquid by driving the circulation pump, wherein the control device, the defrosting operation to melt frost adhering to the air heat source heat exchanger of the second heat pump circuit, the first When driving a heat pump circuit, said performs flow path in the switching valve in the first defrosting operation Ru changeover example, the when the not driven first pump circuit, the flow path by the switching valve is in not a changeover e composite source heat pump device being characterized in that to perform the second defrosting operation to raise the discharge temperature of the second compressor. The first is in the defrosting operation, so as to reduce the rotational speed of the heating circulation pump, wherein the second defrost operation, the composite of claim 1, wherein the driving stop the heating circulation pump Heat source heat pump device.

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