JP2019215134A - Composite heat source heat pump device - Google Patents

Abstract

To provide a composite heat source heat pump device enabling efficient operation suitable for an installation environment.SOLUTION: A composite heat source heat pump device includes: a first heat pump circuit 40 having a first compressor 43 and a first heat source side heat exchanger 46 enabling heat exchange with a prescribed heat source different from the outside air; a second heat pump circuit 50 having a second compressor 53 and a second heat source side heat exchanger 57 enabling heat exchange with the outside air; outside air temperature detection means 52c; and a control device 6. The control device 6 sets one of the first compressor 43 and the second compressor 53 as a main power source and sets the other of the first compressor and the second compressor as an auxiliary power source with an outside air temperature detected by the outside air temperature detection means 52c as a reference, sets the second compressor 53 as a main power source when the outside air temperature is equal to or more than a prescribed changeover temperature, and sets the first compressor 43 as a main power source when the outside air temperature is less than the prescribed changeover temperature, and performs heating operation. In the composite heat source heat pump device, determination means 62a for determining easiness of executing defrosting operation is provided, and the determination means 62a sets a prescribed changeover temperature in accordance with the easiness of executing defrosting operation.SELECTED DRAWING: Figure 6

Description

  The present invention relates to a combined heat source heat pump device that sets a switching temperature for switching between a main power source and an auxiliary power source in accordance with the ease of execution of a defrosting operation.

  Conventionally, in a composite heat source heat pump device of this type, when a first heat pump circuit that exchanges heat with a heat medium and a second heat pump circuit that has an air heat exchanger that exchanges heat with outside air are used together, the outside air temperature and a predetermined switching temperature In comparison with the above, there is a type in which the compressor of one of the heat pump circuits is used as a main power source and the compressor of the other heat pump circuit is used as an auxiliary power source to perform drive control. (For example, refer to Patent Document 1.)

JP 2015-117880 A

  By the way, in this conventional device, the switching temperature is a fixed temperature set in advance for the heat pump circuit having the compressor serving as the main power source to efficiently collect heat from the heat source. It is a situation in which the air heat exchanger of the second heat pump circuit is not frosted and the defrosting operation is hardly performed, for example, due to low humidity inside, and the efficiency of the second heat pump circuit is higher than the efficiency of the first heat pump circuit. Even in this case, when the switching temperature is a fixed temperature and the outside air temperature is lower than the switching temperature, the main power source is determined to be the compressor of the first heat pump circuit, and the compressor of the second heat pump circuit is Does not become the main power source, the operation efficiency does not increase, and conversely, the humidity in the outside air is high, so that the air heat exchanger of the second heat pump circuit is easily frosted and the defrosting operation is easily performed. In such a situation, even when the efficiency of the second heat pump circuit is lower than the efficiency of the first heat pump circuit, if the switching temperature is a fixed temperature and the outside air temperature is higher than the switching temperature, the main power source Is determined as the compressor of the second heat pump circuit, the compressor of the first heat pump circuit does not become the main power source, and the operating temperature does not increase. Therefore, it is not appropriate to switch the main power source / auxiliary power source, and there is a possibility that the operating efficiency is reduced.

  In order to solve the above problems, the present invention provides a first compressor, a first load-side heat exchanger, a first expansion valve, and a second heat exchanger capable of performing heat exchange with a predetermined heat source different from outside air. A first heat pump circuit having one heat source side heat exchanger, a second compressor, a second load side heat exchanger, a second expansion valve, and a second heat source side heat exchanger capable of exchanging heat with the outside air are provided. A second heat pump circuit, an outside air temperature detecting means for detecting an outside air temperature, and a control device for controlling an operation, wherein the control device performs the operation based on the outside air temperature detected by the outside air temperature detecting means. One of the first compressor and the second compressor is set as a main power source, and the other is set as an auxiliary power source. When the outside air temperature is equal to or higher than a predetermined switching temperature, the second compressor is set as a main power source. When the outside air temperature is lower than the predetermined switching temperature, the first compressor is used as a main power source. In the combined heat source heat pump device that performs the heating operation in a fixed manner, the determination unit that determines the easiness of the defrosting operation for melting the frost attached to the second heat source side heat exchanger of the second heat pump circuit is provided, The determining means sets the predetermined switching temperature according to the ease with which the defrosting operation is performed.

  Further, in claim 2, when the determination unit determines that the defrosting operation is difficult to be performed, the switching temperature is reduced.

  According to a third aspect of the present invention, when the determination unit determines that the defrosting operation is easily performed, the determination unit increases the switching temperature.

  According to a fourth aspect of the present invention, when the determining unit determines that the defrosting operation is not likely to be performed or hardly performed, the switching temperature is not changed.

  Further, in claim 5, the determination means determines the ease of execution of the defrosting operation based on the execution state of the defrosting operation.

  According to a sixth aspect of the present invention, the determination unit calculates a value calculated based on an operation time of the second heat pump circuit when the outside air temperature is equal to or lower than a predetermined temperature and the number of times or the execution time of the defrosting operation. Thus, the ease of execution of the defrosting operation is determined, and the switching temperature is set according to the calculated value.

  According to the first aspect of the present invention, there is provided a judging means for judging the easiness of executing a defrosting operation for melting frost attached to the second heat source side heat exchanger of the second heat pump circuit. By setting the predetermined switching temperature in accordance with the easiness of the operation, if the environment in which the defrosting operation is likely to be performed, the main power source from the second compressor to the first compressor is used. In the environment where the defrosting operation is unlikely to be performed, the switching timing of the main power source from the second compressor to the first compressor is delayed. Since the switching temperature is automatically set to the switching environment suitable for the installation environment, the operation efficiency can be improved.

  According to the second aspect, when the determination unit determines that the defrosting operation is difficult to be performed, the switching temperature is reduced, so that the defrosting operation is difficult to be performed. If it is difficult to form frost on the side heat exchanger, the second heat pump circuit can be operated with high efficiency by suppressing a decrease in efficiency due to frost, and by lowering the switching temperature, the second compressor is driven by the main power source. And the switching timing of the main power source from the second compressor to the first compressor is delayed, so that the ratio of driving the second compressor as the main power source increases, and the operating efficiency is improved. Can be done.

  According to the third aspect, when the determination unit determines that the defrosting operation is easily performed, the switching temperature is increased, so that the defrosting operation is easily performed, that is, the second heat source. If the side heat exchanger is easily frosted, the efficiency of the second heat pump circuit is reduced due to frosting and high efficiency operation cannot be performed. However, by increasing the switching temperature, the first compressor is set as the main power source. In addition, the switching timing of the main power source from the second compressor to the first compressor is advanced, so that the rate at which the second compressor is driven as the main power source is reduced, and the efficiency is reduced due to frost formation. Driving is reduced and driving efficiency can be improved.

  According to the fourth aspect, when the determination unit determines that the defrosting operation is not easily performed or hardly performed, the determining unit does not change the switching temperature. Can be maintained, so that a state in which the operation efficiency is good can be maintained.

  According to the fifth aspect, the determining means determines the ease of execution of the defrosting operation based on the execution state of the defrosting operation. From the number of executions of the frost operation, the execution time of the defrost operation, etc., it is possible to reliably determine the ease of execution of the defrost operation in each installation environment, and based on the determination, set a switching temperature suitable for each installation environment. Can be easily performed.

  Further, according to claim 6, the determining means calculates the operation time of the second heat pump circuit when the outside air temperature is equal to or lower than the predetermined temperature and the number of times or the execution time of the defrosting operation, or the calculated value based on the execution time. By determining the ease of execution of the defrosting operation, and by setting the switching temperature in accordance with the calculated value, under an outside air temperature condition in which frost easily adheres to the second heat source side heat exchanger. By using the operation time of the second heat pump circuit 50 and the number of executions or the execution time of the defrosting operation, it is possible to reliably determine the ease of execution of the defrosting operation by a simple calculation, and to perform an appropriate switching corresponding thereto. The temperature can be set.

FIG. 1 is an external configuration diagram illustrating main units of a composite heat source heat pump device according to an embodiment of the present invention. The schematic block diagram which shows the whole structure of a composite heat source heat pump apparatus. The figure which shows the switching temperature of the main power source / auxiliary power source of a composite heat source heat pump apparatus. Explanatory drawing explaining operation | movement at the time of heating operation. Explanatory drawing explaining the operation | movement when a defrost driving | operation is performed during a heating driving | operation. 5 is a flowchart illustrating a method for setting a switching temperature for switching between a main power source and an auxiliary power source. The figure which shows the relationship between the defrosting frequency coefficient of the parameter | index showing the ease of performing a defrosting operation, and the switching temperature change amount. The figure explaining an example of the switching temperature transition of the main power source / auxiliary power source. The figure explaining other examples of the switching temperature transition of the main power source / auxiliary power source. The figure explaining further another example of the switching temperature transition of the main power source / auxiliary power source.

The configuration of the composite heat source heat pump device 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 an underground 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 is provided. In addition, the composite heat source heat pump device 1 operates the load-side circulation circuit 30 that circulates the load-side circulating liquid L (for example, water or antifreeze) to the air conditioning terminal 36, the heat source-side circulation circuit 20, and the operation of the composite heat source heat pump device 1. It has a control device 6 (61, 62) as a control means for controlling and a remote controller 60 for sending a signal to the control device 6, and performs heating or cooling of the room where the air conditioning terminal 36 is installed.

  As shown in FIG. 2, the combined heat source heat pump device 1 according to the present embodiment heats or cools the load-side circulating fluid L on the air conditioning terminal 36 side using a heat source different from outside air, here, an underground heat source. A first load side heat exchanger 41 of the first heat pump circuit 40 and a second load side heat exchange of the second heat pump circuit 50 for heating or cooling the load side circulating fluid L on the air conditioning terminal 36 side using outside air as a heat source. The first load-side heat exchanger 41 is disposed upstream of the second load-side heat exchanger 51 with respect to the flow of the load-side circulating liquid L that circulates in the load-side circulation circuit 30 with the heat exchanger 51. . The composite heat source heat pump device 1 can function as a heating device and a cooling device. In this embodiment, components and operations when mainly used as a heating device will be described.

  The first heat pump circuit 40 includes a first compressor 43 having a variable number of revolutions for compressing the first refrigerant C1, a first four-way valve 44, a first load-side heat exchanger 41, and a first pressure reducing means. It is configured to include an expansion valve 45, a first heat source side heat exchanger 46, and a first refrigerant pipe 42 that connects them in a ring shape.

  The first four-way valve 44 provided in the first refrigerant pipe 42 has a function as a switching valve for switching the flow direction of the first refrigerant C1 in the first heat pump circuit 40, and is discharged from the first compressor 43. A state in which the first refrigerant C1 is circulated in the order of the first load side heat exchanger 41, the first expansion valve 45, and the first heat source side heat exchanger 46 to form a flow path returning to the first compressor 43 (heating operation). State) and the first refrigerant C1 discharged from the first compressor 43 flows in the order of the first heat source side heat exchanger 46, the first expansion valve 45, and the first load side heat exchanger 41, The state can be switched to a state in which a flow path returning to one compressor 43 is formed (a state during cooling operation).

  In the underground heat pump unit 4 shown in FIG. 2, reference numeral 42a denotes a first refrigerant discharge temperature sensor for detecting the temperature of the first refrigerant C1 discharged from the first compressor 43, and reference numeral 42b denotes a first refrigerant discharge temperature sensor. A first refrigerant pipe 42 is provided in the first refrigerant pipe 42 from the first expansion valve 45 to the first heat source side heat exchanger 46 and detects the temperature of the first refrigerant C1 on the low pressure side (during heating operation) or the high pressure side (during cooling operation). 1 is a refrigerant temperature sensor.

  The second heat pump circuit 50 includes a variable-speed second compressor 53 that compresses the second refrigerant C2, a second four-way valve 54, a second load-side heat exchanger 51, and a second pressure-reducing unit. An expansion valve 55, an air heat exchanger 57 as a second heat source side heat exchanger for exchanging heat with the outside air sent by the operation of the blower fan 56, and a second refrigerant pipe 52 for connecting these in a ring shape are provided. It is configured.

The second four-way valve 54 provided in the second refrigerant pipe 52 has a function as a switching valve for switching the flow direction of the second refrigerant C2 in the second heat pump circuit 50, and is discharged from the second compressor 53. A state in which the second refrigerant C2 is circulated in the order of the second load side heat exchanger 51, the second expansion valve 55, and the air heat exchanger 57 to form a flow path returning to the second compressor 53 (a state during the heating operation). ) And the second refrigerant C2 discharged from the second compressor 53 flows through the air heat exchanger 57, the second expansion valve 55, and the second load-side heat exchanger 51 in this order, and returns to the second compressor 53. It can be switched to a state in which a flow path is formed (during a defrosting operation or a cooling operation).
In the present embodiment, when the temperature of the air heat exchanger 57 becomes low and frost is formed, the second refrigerant C2 discharged from the second compressor 53 flows toward the air heat exchanger 57 so that the second four-way valve 54 is formed. Is switched, and the frost generated in the air heat exchanger 57 is melted by the high-temperature second refrigerant C2 from the second compressor 53.

  Further, in the air heat heat pump unit 5 shown in FIG. 2, reference numeral 52a is a second refrigerant discharge temperature sensor for detecting the temperature of the second refrigerant C2 discharged from the second compressor 53, and reference numeral 52b is a second refrigerant discharge temperature sensor. It is provided in the second refrigerant pipe 52 from the expansion valve 55 to the air heat exchanger 57, and detects the temperature of the second refrigerant C2 on the low pressure side (during the heating operation) or the high pressure side (during the defrost operation or the cooling operation). A second refrigerant temperature sensor 52c is an outside air temperature sensor as outside air temperature detecting means for detecting the outside air temperature.

  In addition, as the refrigerant of the first heat pump circuit 40 and the second heat pump circuit 50, any refrigerant such as HFC refrigerant such as R410A and R32 and carbon dioxide refrigerant can be used.

  The first load-side heat exchanger 41, the first heat source-side heat exchanger 46, and the second load-side heat exchanger 51 are configured by, for example, a plate-type heat exchanger. In this plate heat exchanger, a plurality of heat transfer plates are stacked, and a refrigerant flow path for flowing a refrigerant and a fluid flow path for flowing a fluid such as a circulating liquid are formed alternately at each heat transfer plate. ing.

  The heat-source-side circulation circuit 20 serves as a heat-source-side circulation pump 22 having a variable number of revolutions, a first heat-source-side heat exchanger 46, and a heat source that exchanges heat with the first refrigerant C1 flowing through the first heat-source-side heat exchanger 46. The underground heat exchanger 23 installed (in the ground in this example) is connected in a ring shape by a heat source side pipe 21 as a heat medium pipe. The heat source side circulating pump 22 circulates the heat source side circulating fluid H (water or antifreeze) as a heat medium in the heat source side piping 21 and stores the heat source side circulating fluid H to reduce the pressure of the heat source side circulating circuit 20. A heat source side cistern 24 to be adjusted is provided.

  The load-side circulation circuit 30 includes a first load-side heat exchanger 41, a second load-side heat exchanger 51, and an air-conditioning terminal 36 as a load terminal such as a floor heating panel, a panel convector, or a fan coil. The side pipes 31 are connected annularly in order from the upstream side. The load-side pipe 31 is provided with a load-side circulating pump 32 that circulates the load-side circulating fluid L to the load-side circulating circuit 30. Each of the load-side pipes 31 branched for each air conditioning terminal 36 has A thermal valve 33 for controlling the supply of the load side circulating fluid L to the air conditioning terminal 36 by opening and closing is provided, and the thermal valve 33 is provided so that the room temperature in the room where the air conditioning terminal 36 is installed becomes a predetermined temperature. Opening and closing are controlled, and are provided outside the air conditioning terminal 36 in FIG. 2, but may be built in the air conditioning terminal 36. Although two air conditioning terminals 36 are provided in FIG. 2, one or three or more air conditioning terminals may be provided, and the number and specifications are not particularly limited.

  Further, in the load-side circulation circuit 30 shown in FIG. 2, reference numeral 34 denotes a return provided in the load-side pipe 31 for detecting the temperature of the load-side circulating fluid L flowing into the first load-side heat exchanger 41 from the air conditioning terminal 36. Reference numeral 35 denotes a load-side cistern that stores the load-side circulating fluid L and adjusts the pressure of the load-side circulation circuit 30.

  The control device 6 includes an underground heat pump control device 61 that controls the operation of the heat source side circulation circuit 20, the load side circulation circuit 30, and the first heat pump circuit 40, and an air heat heat pump that controls the operation of the second heat pump circuit 50. And a control device 62. The control device 6 includes a storage unit that stores various data and programs, and a control unit that performs arithmetic and control processes. The control device 6 receives signals from a temperature sensor such as an outside air temperature sensor 52c and a remote controller 60, The operation of the composite heat source heat pump device 1 can be controlled.

  Here, the underground heat heat pump control device 61 during the heating operation will be described. The underground heat heat pump control device 61 detects the temperature of the load-side circulating fluid L immediately upstream of the first load-side heat exchanger 41. The rotation speed of the first compressor 43 is controlled according to the detection value of the return temperature sensor 34. In particular, in this example, the first compressor 43 is set so that the return hot water temperature of the load-side circulating fluid L detected by the return temperature sensor 34 becomes the target hot water temperature set based on the set temperature of the remote controller 60, for example. To control the number of revolutions.

  The underground heat pump control device 61 controls the opening degree of the first expansion valve 45 in accordance with the refrigerant discharge temperature of the first refrigerant C1 detected by the first refrigerant discharge temperature sensor 42a. In particular, in this example, the first expansion is performed so that the refrigerant discharge temperature of the first refrigerant C1 detected by the first refrigerant discharge temperature sensor 42a becomes the control target refrigerant discharge temperature corresponding to the set temperature of the remote controller 60, for example. The valve opening of the valve 45 is controlled.

  Further, the underground heat heat pump control device 61 controls the rotation speed of the heat source side circulation pump 22 according to the temperature of the first refrigerant C1 detected by the first refrigerant temperature sensor 42b. In particular, in this example, the rotation speed of the heat source side circulation pump 22 is controlled such that the temperature of the first refrigerant C1 detected by the first refrigerant temperature sensor 42b becomes a substantially constant value.

  Then, the underground heat heat pump control device 61 controls the rotation speed of the load-side circulation pump 32. In particular, in this example, when only the heating operation is performed, the rotation speed of the load-side circulation pump 32 is controlled so as to rotate at a constant speed (constant rotation speed). When the defrosting operation is performed, the rotation speed of the load-side circulating pump 32 is controlled at a predetermined defrost rotation speed that is lower than the predetermined rotation speed during the heating operation.

  Further, the underground heat heat pump control device 61 determines which of the underground heat pump unit 4 and the air heat heat pump unit 5 has higher thermal efficiency (heat collecting efficiency) based on the outside air temperature detected by the outside air temperature sensor 52c. Then, the one with higher thermal efficiency is set as the main side (priority side) heat pump unit, and the one with lower thermal efficiency is set as the auxiliary side heat pump unit. In other words, the underground heat heat pump control device 61 determines the first compressor 43 and the air heat heat pump unit 5 of the underground heat heat pump unit 4 (the first heat pump circuit 40) based on the outside air temperature detected by the outside air temperature sensor 52c. One of the second compressors 53 of the (second heat pump circuit 50) is set as a main power source, and the other is set as an auxiliary power source.

Here, the switching of the main power source / auxiliary power source will be described with reference to FIG.
First, as a basic idea, when the outside air temperature is relatively low in winter or the like, there is a problem that the air heat exchanger 57 is frosted by absorbing heat from the outside air, so that the first compressor 43 And the second compressor 53 is used as an auxiliary power source. Conversely, when the outside air temperature is not so low even in the autumn, spring, or winter, the second compressor 53 is used as the main power source because the air heat exchanger 57 is less likely to frost even if it absorbs heat from the outside air. Then, the first compressor 43 is used as an auxiliary power source.

  That is, in the present embodiment, when the outside air temperature detected by the outside air temperature sensor 52c is lower than the predetermined switching temperature θ1 (here, θ1 = 5 ° C.) when starting the heating operation, the first heat pump circuit 40 The heating operation is started using the first compressor 43 as a main power source and the second compressor 53 of the second heat pump circuit 50 as an auxiliary power source. When the outside air temperature detected by the outside air temperature sensor 52c is equal to or higher than the predetermined switching temperature θ1, the second compressor 53 of the second heat pump circuit 50 is used as a main power source and the first compression of the first heat pump circuit 40 is used. The heating operation is started using the electric machine 43 as an auxiliary power source.

  Then, in the present embodiment, when the outside air temperature changes after the heating operation is started as described above, the main power source and the auxiliary power source are appropriately replaced according to the degree of the change. In other words, the power source of the first compressor 43 and the power source of the second compressor 53, which is the main power source or the auxiliary power source, is switched.

  That is, after the first compressor 43 starts the heating operation as the main power source and the second compressor 53 starts the heating operation as the auxiliary power source (when the outside air temperature at the start of the heating operation is less than θ1), as shown in FIG. Until the temperature rises to or above the switching temperature θ1 (5 ° C.) (less than 5 ° C.), the upper first compressor 43 is used as the main power source and the second compressor 53 is used as the auxiliary power source. Thereafter, when the outside air temperature rises to θ1 or more, the second compressor 53 is used as a main power source, and the first compressor 43 is used as an auxiliary power source.

  Conversely, after the second compressor 53 starts the heating operation as the main power source and the first compressor 43 starts the heating operation as the auxiliary power source (when the outside air temperature at the start of the heating operation is θ1 or more), as shown in FIG. As long as the outside air temperature does not drop below θ2 (here, θ2 = 2 ° C.) (in the case of 2 ° C. or higher), the second compressor 53 is used as the main power source and the first compressor 43 is used as the auxiliary power source. Thereafter, when the outside air temperature falls below θ2, the first compressor 43 is used as a main power source, and the second compressor 53 is used as an auxiliary power source.

  That is, during the heating operation, as indicated by the arrow in FIG. 3, in the above-described rising direction of the outside air temperature, the switching temperature serving as a breakpoint for switching between the main power source and the auxiliary power source is set to θ1, while the outside air temperature is changed. In the decreasing direction, the switching temperature is changed to θ2 (= the switching behavior of the main power source / auxiliary power source has hysteresis). Note that, as the switching temperature, θ1 = 5 ° C. and θ2 = 2 ° C. are stored in the storage unit of the control device 6 as preset initial values.

  As described above, when the outside air temperature changes and it is considered that it is more efficient to change the assignment of the main power source and the auxiliary power source up to that time, the first compressor 43 and the second compressor 53 The assignment is changed, and the compressor that was the main power source is driven as the auxiliary power source, and the compressor that was the auxiliary power source is driven as the main power source.

  In this embodiment, the underground heat heat pump control device 61 has been described as performing the switching control of the main power source / auxiliary power source. However, the air heat heat pump control device 62 performs the switching of the main power source / auxiliary power source. The underground heat heat pump control device 61 and the air heat heat pump control device 62 may control the switching of the main power source / auxiliary power source in cooperation with each other as necessary. There may be.

  Next, the air heat heat pump control device 62 during the heating operation will be described. The air heat heat pump control device 62 controls the rotation speed of the second compressor 53 according to the detection value of the return temperature sensor 34. Particularly, in this example, the return temperature of the second compressor 53 is set such that the return hot water temperature of the load-side circulating fluid L detected by the return temperature sensor 34 becomes the target hot water temperature set based on the set temperature of the remote controller 60, for example. Control the speed. The air heat pump control device 62 and the underground heat pump control device 61 control the target first compressor 43 or the second compressor 53 while cooperating with each other as necessary.

  The air heat pump control device 62 controls the valve opening of the second expansion valve 55 according to the refrigerant discharge temperature of the second refrigerant C2 detected by the second refrigerant discharge temperature sensor 52a. In particular, in this example, the second expansion is performed so that the refrigerant discharge temperature of the second refrigerant C2 detected by the second refrigerant discharge temperature sensor 52a becomes the control target refrigerant discharge temperature corresponding to the set temperature of the remote controller 60, for example. The valve opening of the valve 55 is controlled. The air heat heat pump control device 62 and the underground heat heat pump control device 61 control the target first expansion valve 45 or the second expansion valve 55 while cooperating with each other as necessary.

  Further, the air heat pump control device 62 controls the rotation speed of the blower fan 56 according to the outside air temperature detected by the outside air temperature sensor 52c.

  Then, when the air heat heat pump control device 62 determines that frost is attached to the air heat exchanger 57 during the heating operation, the air heat heat pump control device 62 performs a defrost operation to melt the frost.

  The mode of the defrosting operation is a mode in which the second refrigerant C2 is circulated in a direction opposite to that of the heating operation. Specifically, the defrosting operation is performed by setting the second expansion valve 55 to a heating operation before the defrosting operation. While expanding to a predetermined opening degree (for example, fully open), the second four-way valve 54 is switched to the state during the defrosting operation, and the flow direction of the second refrigerant C2 is opposite to the flow direction of the second refrigerant C2 during the heating operation. The second refrigerant C2 discharged from the second compressor 53 is directly supplied to the air heat exchanger 57 to melt the frost generated in the air heat exchanger 57. The second refrigerant C2, whose temperature has been reduced by heat exchange with frost in the air heat exchanger 57, passes through the second expansion valve 55 without being depressurized by the second expansion valve 55, and passes through the second load-side heat exchanger 51. And returns to the second compressor 53 again.

  The start of the defrosting operation is, for example, whether or not the refrigerant temperature detected by the second refrigerant temperature sensor 52b has reached a preset defrosting start temperature, or the outside air temperature detected by the outside air temperature sensor 52c and the second temperature. (2) The control device 6 (for example, the air heat heat pump control device 62) determines whether the refrigerant temperature detected by the refrigerant temperature sensor 52b has reached a preset defrost start temperature, that is, a predetermined defrost. The control device 6 determines whether or not the start condition is satisfied, and when it is determined that the defrost start condition is satisfied, the defrost operation can be started. Completion of the defrosting operation is based on whether the temperature of the second refrigerant C2 flowing through the air heat exchanger 57 detected by the second refrigerant temperature sensor 52b has reached a preset defrost end temperature. The controller 6 (for example, the air heat heat pump controller 62) makes a determination, that is, the controller 6 determines whether or not a predetermined defrost end condition is satisfied. The operation can be ended.

  In addition, the air heat heat pump control device 62 includes a determination unit 62a that determines the easiness of performing the defrosting operation for melting the frost attached to the air heat exchanger 57, and the determination unit 62a performs the defrosting operation. The predetermined switching temperatures (θ1, θ2) are changed according to the ease. Specific control contents of the determination means 62a will be described later.

  In the present embodiment, the air heat heat pump control device 62 has the determination means 62a. However, the underground heat heat pump control device 61 has a determination means having the same function as the determination means 62a. Alternatively, the underground heat heat pump control device 61 and the air heat heat pump control device 62 may cooperate with each other as needed to exhibit the same function as the determination unit 62a.

  Next, the operation of the combined heat source heat pump device 1 shown in FIGS. 1 and 2 during the heating operation will be described with reference to FIGS. 4 and 5. The heating operation for heating the load-side circulating fluid L supplied to the air-conditioning terminal 36 is performed by operating one of the first heat pump circuit 40 and the second heat pump circuit 50, and when the first heat pump circuit 40 and the second heat pump circuit There is a case where the operation is performed by operating both of the heat pump circuits 50. Here, a case where the operation is performed by operating both the first heat pump circuit 40 and the second heat pump circuit 50 will be described. The arrows in FIGS. 4 and 5 indicate the directions in which the refrigerant and the circulating liquid flow.

  When the indoor heating is instructed by the air-conditioning terminal 36 from the remote controller 60, first, the controller 6 sets the first compressor 43 of the underground heat pump unit 4 and the second compressor of the air heat pump unit 5 based on the outside air temperature. One of the two compressors 53 is set as a main power source, and the other is set as an auxiliary power source.

  Specifically, if the outside air temperature detected by the outside air temperature sensor 52c is equal to or higher than a predetermined switching temperature θ1 (for example, 5 ° C.), it is determined that the air heat heat pump unit 5 has higher heat collection efficiency, and the second compression When the outside air temperature detected by the outside air temperature sensor 52c is lower than the predetermined switching temperature θ1 (for example, 5 ° C.), the underground The heat heat pump unit 4 determines that the heat collection efficiency is higher, and sets the first compressor 43 as the main power source and sets the second compressor 53 as the auxiliary power source.

  Then, the control device 6 switches the flow path so that the first four-way valve 44 and the second four-way valve 54 are in the state of the heating operation, and the first compressor 43, the first expansion valve 45, the heat source side circulation pump 22 The second compressor 53, the second expansion valve 55, the blower fan 56, and the load-side circulation pump 32 are driven to start the heating operation. At this time, the thermal valve 33 is also opened.

  During the heating operation, in the first heat pump circuit 40, the high-temperature and high-pressure gaseous first refrigerant C1 compressed by the first compressor 43 is discharged from the first compressor 43, and the first refrigerant C1 serves as a condenser. In the functioning first load-side heat exchanger 41, heat is exchanged with the load-side circulating fluid L flowing through the load-side circulating circuit 30 to release heat to the load-side circulating fluid L and heat the gas-liquid mixed state. Changes to high-pressure refrigerant. Then, the first refrigerant C1 in this state is reduced in pressure in the first expansion valve 45 to become a low-pressure refrigerant and easily vaporized. In the first heat source side heat exchanger 46 functioning as an evaporator, the heat source side circulation circuit The heat exchange is performed with the heat source side circulating fluid H flowing through 20 to absorb heat from the heat source side circulating fluid H to become a low temperature / low pressure gaseous first refrigerant C <b> 1 and return to the first compressor 43 again.

  On the other hand, in the second heat pump circuit 50, the high-temperature and high-pressure gaseous second refrigerant C2 compressed by the second compressor 53 is discharged from the second compressor 53, and the second refrigerant C2 functions as a condenser. (2) In the load-side heat exchanger 51, heat exchange is performed with the load-side circulating liquid L flowing through the load-side circulation circuit 30, and heat is released to the load-side circulating liquid L, and the high-pressure refrigerant in a gas-liquid mixed state while heating Changes to Then, the second refrigerant C2 in this state is reduced in pressure in the second expansion valve 55, becomes a low-pressure refrigerant, and is easily evaporated, and is sent to the air heat exchanger 57 functioning as an evaporator by the operation of the blower fan 56. The refrigerant exchanges heat with the outside air to absorb heat from the outside air to become a low-temperature, low-pressure gaseous second refrigerant C2, which returns to the second compressor 53 again.

  In the heat source side circulation circuit 20, the underground heat is collected by the underground heat exchanger 23, and the heat source side circulating liquid H bearing the heat is driven by the heat source side circulation pump 22 to the first heat source side heat exchanger 46. Supplied to Then, heat exchange is performed between the first refrigerant C1 and the heat source side circulating liquid H in the first heat source side heat exchanger 46, and the underground heat collected in the underground heat exchanger 23 is transferred to the first refrigerant C1 side. And the first refrigerant C1 is heated and evaporated.

  In the load-side circulation circuit 30, the load-side circulating liquid L flowing into the first load-side heat exchanger 41 by the driving of the load-side circulation pump 32 driven at a constant rotation speed is supplied to the first load-side functioning as a condenser. After being heat-exchanged with the first refrigerant C1 in the heat exchanger 41 and heated, the heat is exchanged with the second refrigerant C2 in the second load-side heat exchanger 51 functioning as a condenser, and further heated, so that the heated load is heated. The side circulating fluid L is then supplied to the air conditioning terminal 36 to heat the room, and the temperature-reduced load-side circulating fluid L radiated by the air conditioning terminal 36 is returned to the first load-side heat exchanger 41 again. Return.

  During the heating operation, when the defrosting operation for melting the frost of the air heat exchanger 57 of the air heat pump unit 5 (second heat pump circuit 50) is performed, the second four-way valve 54 is in the state during the heating operation. From the state of the defrosting operation, and the flow direction of the second refrigerant C2 is opposite to the flow direction of the second refrigerant C2 during the heating operation, as shown in FIG.

  During the defrosting operation, the first heat pump circuit 40 is operated and the load-side circulation pump 32 is also driven, and while supplying heat to the second heat pump circuit 50 for defrosting the air heat exchanger 57, The heating operation can be continued so that a stable heating capacity is secured and the hot water temperature of the load side circulating fluid L supplied to the air conditioning terminal 36 is not lowered.

  Next, as a characteristic operation, a method of setting a switching temperature for switching the main power source / auxiliary power source by the determination means 62a will be described with reference to the flowchart of FIG.

  The judging means 62a grasps the operation status of the air heat heat pump unit 5 (second heat pump circuit 50) and the execution status of the defrosting operation during a predetermined period (for example, three days), and based on the information, the main power source / auxiliary. This is for setting the switching temperature of the power source. First, the determination means 62a starts a timer for counting the predetermined period (step S1).

  Subsequently, the judging means 62a judges whether or not the outside air temperature detected by the outside air temperature sensor 52c is lower than a predetermined temperature (for example, lower than 5 ° C. as a condition in which frost easily adheres to the air heat exchanger 57) ( In step S2), when it is determined that the outside air temperature is lower than the predetermined temperature, the operation time [minute] of the second heat pump circuit 50 (air heat pump unit 5) when the outdoor air temperature is lower than the predetermined temperature is counted (integrated). The number of times the defrosting operation has been performed is counted (step S3), and the process proceeds to step S4 described below. The operation time of the second heat pump circuit 50 (air heat pump unit 5) counted in the process of step S3 is a time when only the second heat pump circuit 50 is operated to perform the heating operation, and Both the operation time of the second heat pump circuit 50 when the heating operation is performed by operating both the first heat pump circuit 40 and the second heat pump circuit 50 are included. On the other hand, if it is determined in step S2 that the outside air temperature is equal to or higher than the predetermined temperature, the process proceeds to step S4 described below.

  Then, the determining means 62a determines whether or not a predetermined period (three days) has elapsed (step S4). If it is determined that the predetermined period has not elapsed, the process returns to step S2 and the predetermined period is determined. Until the time elapses, the processes of steps S2 and S3 are repeated. When it is determined that the predetermined period has elapsed, it is determined whether the operation time (integrated operation time) of the second heat pump circuit 50 is equal to or longer than a predetermined time (for example, 6 hours). Then, if it is determined that the operation time of the second heat pump circuit 50 is equal to or longer than the predetermined time (step S5), the operation time of the second heat pump circuit 50 and the number of executions of the defrosting operation counted in the processing of step S3 are determined. , A defrosting frequency coefficient, which is an index indicating the ease with which the defrosting operation is performed, is calculated (step S6), and the main power source / auxiliary power source is switched from the calculated value. Degrees (.theta.1, .theta.2) Set (step S7), and resets the timer that has been subjected to counting of a predetermined time period (step S8), and the process returns to step S1. When the determining means 62a determines that the operation time of the second heat pump circuit 50 is less than the predetermined time in the process of step S5, the switching temperature (θ1, θ2) currently set is maintained ( Step S9) and proceed to the processing of step S8.

Here, a method of calculating the above defrost frequency coefficient and a method of setting the switching temperature (θ1, θ2) of the main power source / auxiliary power source from the calculated value will be described. The defrost frequency coefficient is calculated by the following equation (1).
Defrost frequency coefficient = second heat pump circuit 50 operating time / number of executions of defrost operation (Equation 1)

  Subsequently, the determination unit 62a compares the calculated defrost frequency coefficient with the relationship between the defrost frequency coefficient and the switching temperature change amount as shown in FIG. Thus, the switching temperature of the main power source / auxiliary power source is set. As shown in FIG. 7, the defrost frequency coefficient cannot be calculated when the calculated defrost frequency coefficient exceeds a predetermined reference range (90 or more and less than 120) and is 120 or more (when the number of times of the defrost operation is 0). However, in this case, the defrosting frequency coefficient is assumed to be programmed in advance so that a value of 120 or more is automatically calculated.), The determining unit 62a determines that the defrosting operation is difficult to be performed, The switching temperature (θ1, θ2) is changed by 1 ° C. from the main power source / auxiliary power source switching temperature (θ1, θ2) which is currently set as the current value, and the calculated defrost frequency coefficient is used as a reference. When the value is within the range of 90 or more and less than 120, the determination unit 62a determines that the defrosting operation is not easily performed or hardly performed, and the main power source / auxiliary power source currently set as the current value is switched. Temperature (θ1, θ2) If the calculated defrost frequency coefficient is less than 90, which is below a preset reference range (90 or more and less than 120), the determination unit 62a determines that the defrost operation is easy to be performed, and determines the current value as the current value. The switching temperature (θ1, θ2) is changed so as to increase by 1 ° C. from the set main power source / auxiliary power source switching temperature (θ1, θ2).

  Next, a specific example of the transition temperature transition between the main power source and the auxiliary power source will be described with reference to FIGS. Note that (a) the first period, (b) the second period, (c) the third period, and (a) the first period and (b) the second period in FIGS. 8 to 10, the integrated operation time of the second heat pump circuit 50 is described as the operation time (minute), and the number of times of the defrosting operation is executed. Expressed as the number of frosts.

  First, in the first period of FIG. 8A, the switching temperature of the main power source / auxiliary power source is detected by the outside air temperature sensor 52c in a state where, for example, θ1 = 5 ° C. and θ2 = 2 ° C. When the outside air temperature was lower than the predetermined temperature (5 ° C.), the operation time of the second heat pump circuit 50 (air heat pump unit 5) involved in the heating operation was 360 minutes, and the number of times of the defrosting operation was three. In this case, the determining means 62a determines that (a) the operation time of the second heat pump circuit 50 is equal to or longer than a predetermined time (6 hours) in the first period, and the defrost frequency coefficient is determined based on the above-described equation (1). Frequency coefficient = 360/3 = 120, and it is determined from the calculated value that the installation environment is such that the defrosting operation is difficult to execute, and the relationship between the defrosting frequency coefficient and the switching temperature change amount as shown in FIG. , The current switching temperature (θ1 = 5 , Θ2 = 2 ℃) 1 ℃ lowered from the next (b) a switching temperature of the second period .theta.1 = 4 ° C., is set to .theta.2 = 1 ° C..

  Then, in the state where the switching temperature of the main power source / auxiliary power source is set to θ1 = 4 ° C. and θ2 = 1 ° C. in the second period of FIG. 8B, the outside air temperature detected by the outside air temperature sensor 52c. Is less than the predetermined temperature (5 ° C.), when the operation time of the second heat pump circuit 50 (air heat pump unit 5) involved in the heating operation is 420 minutes and the number of executions of the defrosting operation is four, The determining means 62a determines that the operation time of the second heat pump circuit 50 is equal to or longer than a predetermined time (6 hours) in the second period (b). 420/4 = 105, it is determined from the calculated value that the installation environment is not likely to be easily performed or not difficult to perform the defrosting operation, and the current switching temperature (θ1 = 4 ° C., θ2 = 1 ° C.) is determined. Maintain the next (c) switching temperature for the third period The .theta.1 = 4 ° C., is set to .theta.2 = 1 ° C..

Next, an example of transition of the switching temperature of the power source / auxiliary power source shown in FIG. 9 will be described.
In the state where the switching temperature of the main power source / auxiliary power source is set to, for example, θ1 = 5 ° C. and θ2 = 2 ° C. in the first period of FIG. 9A, the outside air temperature detected by the outside air temperature sensor 52c is set. When the temperature is lower than the predetermined temperature (5 ° C.), when the operation time of the second heat pump circuit 50 (air heat pump unit 5) involved in the heating operation is 420 minutes, and the number of times of the defrosting operation is five, The determination means 62a determines that (a) the operation time of the second heat pump circuit 50 is equal to or longer than a predetermined time (6 hours) in the first period, and determines the defrost frequency coefficient based on the above-described equation (1). = 420/5 = 84, and it is determined from the calculated values that the environment is an installation environment in which the defrosting operation is easily performed, and the relationship between the defrosting frequency coefficient and the switching temperature change amount as shown in FIG. 7 is referred to. The current switching temperature (θ1 = 5 ° C., θ2 2 ° C.) 1 ° C. is raised from the switching temperature of the next (b) second period .theta.1 = 6 ° C., set at .theta.2 = 3 ° C..

  Then, in the state where the switching temperature of the main power source / auxiliary power source is set to θ1 = 6 ° C. and θ2 = 3 ° C. in the second period of FIG. 9B, the outside air temperature detected by the outside air temperature sensor 52c. Is less than a predetermined temperature (5 ° C.), when the operation time of the second heat pump circuit 50 (air heat pump unit 5) involved in the heating operation is 400 minutes, and the number of executions of the defrosting operation is four, The determining means 62a determines that the operation time of the second heat pump circuit 50 is equal to or longer than a predetermined time (6 hours) in the second period (b). 40/4 = 100, it is determined from the calculated value that the installation environment is not likely to be difficult to perform the defrosting operation, and the current switching temperature (θ1 = 6 ° C., θ2 = 3 ° C.) Maintain the next (c) switching temperature for the third period .theta.1 = 6 ° C., set at .theta.2 = 3 ° C..

Next, an example of transition of the power source / auxiliary power source switching temperature shown in FIG. 10 will be described.
In the state where the switching temperature of the main power source / auxiliary power source is set at, for example, θ1 = 5 ° C. and θ2 = 2 ° C. in the first period of FIG. When the temperature is lower than the predetermined temperature (5 ° C.), the operation time of the second heat pump circuit 50 (air heat pump unit 5) involved in the heating operation is 240 minutes, and the number of times of the defrosting operation is one, The determining means 62a determines that (a) the operation time of the second heat pump circuit 50 is less than the predetermined time (6 hours) in the first period, and (b) the switching temperature in the next (b) second period is as follows. a) Set the same switching temperature θ1 = 5 ° C. and θ2 = 2 ° C. as in the first period.

  As described above, the determination unit 62a sets the switching temperatures (θ1, θ2) in accordance with the ease with which the defrosting operation is performed, thereby providing an environment in which the defrosting operation is likely to be performed. If so, the switching timing of the main power source from the second compressor 53 of the air heat heat pump unit 5 to the first compressor 43 of the underground heat heat pump unit 4 is advanced, so that the defrosting operation is difficult to be performed. In such an environment, the main power source from the second compressor 53 of the air heat heat pump unit 5 (second heat pump circuit 50) to the first compressor 43 of the underground heat heat pump unit 4 (first heat pump circuit 40) The switching temperature (θ1, θ2) suitable for each installation environment is automatically set, such as by delaying the switching timing, so that the operation efficiency can be improved. A.

  The determination unit 62a determines the ease of execution of the defrosting operation based on the execution state of the defrosting operation in the predetermined period, and thus the execution state of the defrosting operation, that is, the defrosting operation. The ease of execution of the defrosting operation in each installation environment can be reliably determined from the number of executions, the execution time of the defrosting operation, and the like, and based on the determination, the switching temperatures (θ1, θ2) suitable for the individual installation environment. Can be easily set.

  The determining means 62a determines the operation time of the second heat pump circuit 50 when the outside air temperature detected by the outside air temperature sensor 52c is lower than the predetermined temperature during the predetermined period, and the number of times the defrosting operation is performed as the execution state of the defrosting operation. The defrosting frequency coefficient, which is a calculated value calculated based on the above, determines the ease of execution of the defrosting operation, and sets the switching temperatures (θ1, θ2) according to the calculated value. The defrosting can be reliably performed by a simple calculation using the operation time of the second heat pump circuit 50 and the number of executions of the defrosting operation under an outside air temperature condition in which frost easily adheres to the air heat exchanger 57. It is possible to determine the easiness of the operation and to set an appropriate switching temperature (θ1, θ2) corresponding to it.

  Furthermore, when the determining unit 62a determines that the calculated defrost frequency coefficient exceeds the preset reference range, that is, when it is determined that the defrosting operation is difficult to be performed, the determination unit 62a determines the currently set switching temperature ( θ1, θ2), the defrosting operation is difficult to execute, that is, if it is difficult to form frost on the air heat exchanger 57, the second heat pump circuit 50 suppresses a decrease in efficiency due to frost formation. By operating at high efficiency with a low switching temperature (θ1, θ2), the second compressor 53 of the air heat heat pump unit 5 (second heat pump circuit 50) can be easily set as the main power source. From the second compressor 53 of the air heat heat pump unit 5 (second heat pump circuit 50) to the first compressor 4 of the underground heat heat pump unit 4 (first heat pump circuit 40). Since the switching timing of the main power source is delayed to the proportion of the second compressor 53 of the high efficiency second heat pump circuit 50 is driven as the main power source is increased, it is capable of improving the operating efficiency.

  In addition, when the determining unit 62a determines that the calculated defrost frequency coefficient is lower than the preset reference range, that is, when it determines that the defrosting operation is easy to be performed, the determining unit 62a determines whether the currently set switching temperature is higher. By increasing (θ1, θ2), the defrosting operation is easily performed, that is, if the air heat exchanger 57 is easily frosted, the efficiency of the second heat pump circuit 50 is reduced due to frosting and the second heat pump circuit 50 is high. Although efficient operation is not possible, raising the switching temperature (θ1, θ2) makes it easier for the first compressor 43 of the underground heat pump unit 4 (first heat pump circuit 40) to be set as the main power source, From the second compressor 53 of the air heat pump unit 5 (second heat pump circuit 50) to the first compressor 43 of the underground heat pump unit 4 (first heat pump circuit 40) Since the switching timing of the main power source is advanced, the rate at which the second compressor 53 of the second heat pump circuit 50 having low efficiency is driven as the main power source is reduced, and the operation in a state where the efficiency is reduced due to frosting is reduced, and the operation is performed. The efficiency can be improved.

  In addition, when the determining unit 62a determines that the calculated defrost frequency coefficient is within the preset reference range, that is, when it is determined that the defrosting operation is not easily performed or hardly performed, Since the set switching temperatures (θ1, θ2) are maintained without being changed, the switching temperatures (θ1, θ2) that match the installation environment can be maintained, so that a state in which the operation efficiency is good can be maintained. Things.

  Note that the present invention is not limited to the above-described embodiment. In the present embodiment, the underground heat exchanger 23 is shown as a heat source of the underground heat heat pump unit 4. In addition to medium heat, water heat sources such as lakes, reservoirs, wells, etc. can be used. Any type of heat source can be used as long as it uses a heat source other than the outside air. The heat source side circulating fluid H supplied to the heat source side circulating fluid H may not be in a form circulating in a closed circuit such as the heat source side circulating circuit 20. It may be of an open type that is discharged to the outside.

  Further, in the present embodiment, the determination means 62a is based on the operation time of the second heat pump circuit 50 and the number of executions of the defrosting operation when the outside air temperature detected by the outside air temperature sensor 52c is lower than the predetermined temperature during the predetermined period. The defrosting frequency coefficient, which is an index indicating the ease with which the defrosting operation is performed, is calculated using Equation 1, but instead of the number of times the defrosting operation is performed, the defrosting operation is performed as the defrosting operation execution status. The defrost frequency coefficient may be calculated using the execution time of the second heat pump circuit 50 when the outside air temperature detected by the outside air temperature sensor 52c is lower than the predetermined temperature during the predetermined period. The method of calculating the defrost frequency coefficient is not limited to the above formula 1 as long as it is based on the number of times or the execution time of the defrosting operation.

REFERENCE SIGNS LIST 1 composite heat source heat pump device 6 control device 40 first heat pump circuit 41 first load side heat exchanger 43 first compressor 45 first expansion valve 46 first heat source side heat exchanger 50 second heat pump circuit 51 second load side heat Exchanger 52c Outside air temperature sensor 53 Second compressor 55 Second expansion valve 57 Air heat exchanger 62a Determination means

Claims (6)

  A first heat pump circuit including a first compressor, a first load-side heat exchanger, a first expansion valve, and a first heat-source-side heat exchanger capable of exchanging heat with a predetermined heat source different from outside air; A second heat pump circuit including a two-compressor, a second load-side heat exchanger, a second expansion valve, and a second heat-source-side heat exchanger capable of exchanging heat with the outside air, and an outside-air temperature detecting means for detecting an outside-air temperature And a control device for controlling an operation, wherein the control device drives one of the first compressor and the second compressor based on the outside air temperature detected by the outside air temperature detecting means as a main power. The second compressor is set as a main power source when the outside air temperature is equal to or higher than a predetermined switching temperature, and the second compressor is set when the outside air temperature is lower than the predetermined switching temperature. For a combined heat source heat pump device that performs heating operation with one compressor set as the main power source Determining means for determining whether the defrosting operation for melting the frost attached to the second heat source side heat exchanger of the second heat pump circuit is easily performed. The determining means performs the defrosting operation. A composite heat source heat pump device wherein the predetermined switching temperature is set according to ease.   The composite heat source heat pump device according to claim 1, wherein the determination unit reduces the switching temperature when determining that the defrosting operation is difficult to perform.   3. The combined heat source heat pump device according to claim 1, wherein the determination unit increases the switching temperature when determining that the defrosting operation is easily performed. 4.   The composite according to any one of claims 1 to 3, wherein the determination unit does not change the switching temperature when the determination unit determines that the defrosting operation is not easily performed or hardly performed. Heat source heat pump device.   The composite according to any one of claims 1 to 4, wherein the determination unit determines the ease of execution of the defrosting operation based on an execution state of the defrosting operation. Heat source heat pump device.   The determination unit is configured to perform the defrosting operation based on a calculation value calculated based on an operation time of the second heat pump circuit when the outside air temperature is equal to or lower than a predetermined temperature and the number of times or the execution time of the defrosting operation. The combined heat source heat pump device according to claim 5, wherein the ease of execution is determined, and the switching temperature is set according to the calculated value.

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