JP5367633B2 - Geothermal heat pump device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a geothermal heat pump device, capable of precisely carrying out ice melting operation, by accurately deciding the freeze of a coolant pipe of a heat source side heat exchanging side functioning as an evaporator during load operation. <P>SOLUTION: The geothermal heat pump device includes a timer unit 24 for timing a predetermined unit time when the detected temperature of the coolant temperature detector 10 for detecting the coolant temperature the heat source side heat exchanger side 7 is &le;0 &deg;C and the detected temperature of the outdoor air temperature detector 11 is higher than the detected temperature of the coolant temperature detector 10 during the load operation, an additional value determiner 25 for deciding the additional value according to the temperature difference between the detected temperature of the coolant temperature detector 10 and the detected temperature of the outdoor air temperature detector 11 every predetermined unit time, and the accumulator 26 for accumulating the additive value decided in the additive value determiner 25, the coolant tube 8 in the heat source side heat exchanger 7 side is determined to be freezed and the ice melting operation for flowing high temperature coolant through the coolant pipe 8 and melting ice in the heat source side heat exchanger 7 side is carried out when the accumulated value in the accumulator 26 reaches to a preset set value during the load operation. <P>COPYRIGHT: (C)2012,JPO&amp;INPIT

Description

  The present invention relates to a geothermal heat pump device that uses geothermal heat whose temperature is relatively stable throughout the year through a heat pump.

  Conventionally, in this type of geothermal heat pump device, as shown in FIG. 11, a heat pump in which a compressor 101, a load side heat exchanger 102, an expansion valve 103, and a heat source side heat exchanger 104 are annularly connected by a refrigerant pipe 105. The circuit 106, the underground heat exchanger 107 buried in the ground G, and the underground heat circulation circuit in which the underground heat exchanger 107 and the heat source side heat exchanger 104 are annularly connected by the heat medium pipe 108. 109 and a geothermal circulation pump 110 that circulates the antifreeze liquid as a heat medium in the geothermal circulation circuit 109, and the geothermal heat that is relatively stable throughout the year is collected by the geothermal heat exchanger 107. The load such as the heating operation for heating the air in the air-conditioned space on the load side and the boiling operation for heating hot water by causing the heat source side heat exchanger 104 to function as an evaporator and the load side heat exchanger 102 as a condenser Things to drive There was. (For example, refer to Patent Document 1.)

  In this conventional geothermal heat pump device, if the load operation is continuously performed and heat is continuously collected from the ground G by the geothermal heat exchanger 107, the temperature in the ground G decreases with time. To go. In particular, when heating operation is performed for 24 hours in a cold region in winter, it appears remarkably.

  The load operation is continuously performed, and the temperature in the ground G is lowered, whereby the temperature of the antifreeze liquid flowing from the underground heat exchanger 107 into the heat source side heat exchanger 104 is lowered, for example, about 2 ° C. In this case, the temperature of the refrigerant flowing through the heat source side heat exchanger 104 is 0 ° C. or a minus region.

  Then, the refrigerant pipe 105 on the heat source side heat exchanger 104 side from the expansion valve 103 to the compressor 101, that is, the low-pressure side refrigerant pipe 105 is also in a negative region, and the outside air is in the surface of the low-pressure side refrigerant pipe 105. The water of the ice freezes, and the ice gradually grows and stacks with time.

  However, even if the refrigerant pipe 105 on the low-pressure side freezes and the ice grows and is stacked, the heat exchange capacity in the heat source side heat exchanger 104 does not decrease, and there is nothing about continuing the load operation. There was no problem.

  However, if the refrigerant pipe 105 on the low-pressure side freezes, and the ice grows and is excessively stacked, the ice interferes with the housing containing the heat pump circuit 106, the partition plate in the housing, etc., and the pressing force is thereby reduced. There is a possibility that the refrigerant pipe 105 may be damaged by being applied to the refrigerant pipe 105 on the low pressure side, and functional parts such as the expansion valve 103 may be frozen and damaged. The applicant of the present application has found that when contacting with a partition plate or the like, the vibration of the compressor 101 is transmitted to the casing through ice to generate noise.

  Accordingly, the applicant of the present application previously described in Patent Document 2 below, during the load operation, the refrigerant temperature detected by the refrigerant temperature sensor provided in the refrigerant pipe on the low-pressure side is equal to or less than zero degrees, and is detected by the outside temperature sensor. Measure the time when the outside air temperature is higher than the refrigerant temperature detected by the refrigerant temperature sensor, and if the measured time reaches the preset time, determine that the low-pressure side refrigerant pipe is frozen, A geothermal heat pump device that performs a de-icing operation in which a high-temperature refrigerant is allowed to flow through a refrigerant pipe to provide ice is provided.

JP 2009-236403 A Japanese Patent Application No. 2010-512278

  However, as a result of repeated trials, the inventors of the present application have found that the refrigerant temperature detected by the refrigerant temperature sensor provided in the refrigerant pipe on the low-pressure side is less than zero degrees and the outside air temperature detected by the outside air temperature sensor is detected by the refrigerant temperature sensor. It has been found that even when the measurement time when the temperature is higher than the refrigerant temperature to be measured is the same, the degree of ice stacking in the refrigerant pipe on the low-pressure side, that is, the thickness of the ice varies. As a result, when the measurement time reaches the set time, there is a problem that the ice-free operation is performed wastefully, or the ice is not melted even if the ice-free operation is performed. It was expected.

  Therefore, the present invention does not wastefully perform ice-free operation, and ice does not remain unmelted even after ice-free operation, and accurately determines icing of the refrigerant pipe on the low-pressure side, and the necessary timing. An object of the present invention is to provide a geothermal heat pump device that can perform ice-breaking operation with high accuracy.

  In order to solve the above-mentioned problems, the present invention is particularly configured in claim 1 with a heat pump circuit in which a compressor, a load-side heat exchanger, a pressure reducing means, and a heat-source-side heat exchanger are connected in an annular shape with a refrigerant pipe, A ground heat exchanger embedded in the ground, a ground heat circulation circuit in which the ground heat exchanger and the heat source side heat exchanger are annularly connected by a heat medium pipe, and the ground heat circulation circuit A ground heat circulation pump that circulates the heat medium, a refrigerant temperature detection means that detects a temperature of the refrigerant on the heat source side heat exchanger side, and an outside air temperature detection means that detects an outside air temperature, and the underground heat A geothermal heat pump that collects geothermal heat with an exchanger and causes the heat source side heat exchanger to function as an evaporator and performs load operation to heat the load side by causing the load side heat exchanger to function as a condenser In the apparatus, during the load operation, the refrigerant temperature detecting means Time measuring means for measuring a predetermined unit time when the temperature of the refrigerant to be discharged is equal to or lower than zero degrees and the outside air temperature detected by the outside air temperature detecting means is higher than the refrigerant temperature detected by the refrigerant temperature detecting means; and the predetermined unit time An addition value determining means for determining an added value corresponding to a temperature difference between the refrigerant temperature detected by the refrigerant temperature detecting means and the outside air temperature detected by the outside air temperature detecting means, and the addition determined by the added value determining means. An accumulating means for accumulating values, and an icing determination means for determining that the refrigerant pipe on the heat source side heat exchanger side is frozen when the integrated value in the accumulating means reaches a preset set value, When it is determined by the icing determination means that the refrigerant pipe on the heat source side heat exchanger side is frozen, an ice thawing operation is performed in which the high temperature refrigerant flows through the refrigerant pipe on the heat source side heat exchanger side to defrost. To do .

  Moreover, in Claim 2, in the geothermal heat pump apparatus according to Claim 1, an operation state of the compressor is detected, and a correction for correcting the addition value determined by the addition value determining means according to the operation state. Means are provided, and the integrating means integrates the added values corrected by the correcting means.

  Further, in claim 3, a heat pump circuit in which a compressor, a load-side heat exchanger, a pressure reducing means, a heat source-side heat exchanger are connected in a ring shape with a refrigerant pipe, an underground heat exchanger embedded in the ground, A ground heat circulation circuit in which a ground heat exchanger and the heat source side heat exchanger are annularly connected by a heat medium pipe, a ground heat circulation pump that circulates the heat medium in the ground heat circulation circuit, and A refrigerant temperature detecting means for detecting the temperature of the refrigerant on the heat source side heat exchanger side, and an outside air temperature detecting means for detecting an outside air temperature, collecting ground heat by the underground heat exchanger, In the geothermal heat pump apparatus that performs load operation in which the heat exchanger functions as an evaporator and the load side heat exchanger functions as a condenser to heat the load side, the refrigerant temperature detection is performed during the load operation. The refrigerant temperature detected by the means is less than zero degrees and the outside air temperature A time measuring means for measuring a predetermined unit time when an outside air temperature detected by the detecting means is higher than a refrigerant temperature detected by the refrigerant temperature detecting means; an operating state of the compressor is detected; An addition value determining means for determining an addition value according to the operating state of the compressor, an integration means for integrating the addition value determined by the addition value determination means, and an integration value in the integration means to a preset set value When the temperature reaches, the freezing determination means for determining that the refrigerant pipe on the heat source side heat exchanger side is frozen is provided, and the freezing determination means determines that the refrigerant pipe on the heat source side heat exchanger side is frozen. In such a case, the deicing operation is performed in which the high-temperature refrigerant is allowed to flow through the refrigerant pipe on the heat source side heat exchanger side to defrost.

  Moreover, in Claim 4, in the underground heat pump apparatus as described in any one of Claim 1 to 3, it flows out of the said heat source side heat exchanger instead of the said refrigerant | coolant temperature detection means, and the said underground heat exchange Underground temperature detection means for detecting the temperature of the heat medium flowing into the vessel was provided.

  According to claim 1 of the present invention, when it is determined by the icing determination means that the refrigerant pipe on the heat source side heat exchanger side is frozen during the load operation, the refrigerant pipe on the heat source side heat exchanger side is connected to the refrigerant pipe on the heat source side heat exchanger side. Since the deicing operation is performed to defrost by flowing a high-temperature refrigerant, it is possible to prevent damage to the functional components such as the refrigerant piping and the expansion valve due to freezing of the refrigerant piping on the heat source side heat exchanger side, Generation of noise due to icing of the refrigerant piping on the heat source side heat exchanger side can be prevented in advance.

  Further, when the icing conditions of the refrigerant pipe on the heat source side heat exchanger are met by the time measuring means, the time is measured for a predetermined unit time, and according to the temperature difference between the refrigerant temperature and the outside air temperature every predetermined unit time by the addition value determining means. The addition value determined by the addition value determination means is integrated by the integration means, and the icing determination means is configured to set the integrated value in the integration means to the heat source side heat exchanger side when the integration value reaches a preset set value. It is determined that the refrigerant pipe is frozen, so an additional value that takes into account the temperature difference between the refrigerant temperature and the outside air temperature, which affects the ice stacking speed of the refrigerant pipe on the heat source side heat exchanger side, is used. It is possible to accurately estimate the ice stacking degree of the refrigerant pipe on the heat source side heat exchanger side, and to perform the ice-breaking operation with high accuracy at the necessary timing.

  According to a second aspect of the present invention, there is provided a correcting means for detecting the operating state of the compressor and correcting the added value determined by the added value determining means according to the operating state, and the integrating means is corrected by the correcting means. By integrating the added values, the circulation flow rate of the refrigerant flowing through the refrigerant piping on the heat source side heat exchanger side is estimated from the operating state of the compressor, and the refrigerant piping on the heat source side heat exchanger side is estimated from the circulation flow rate of the refrigerant Since the correction in consideration of the amount of heat absorbed from the surroundings is added to the added value, it is possible to estimate the ice stacking degree of the refrigerant pipe on the heat source side heat exchanger side with higher accuracy.

  According to the third aspect of the present invention, when it is determined by the icing determination means that the refrigerant pipe on the heat source side heat exchanger side is frozen during the load operation, the refrigerant pipe on the heat source side heat exchanger side has a high temperature. Since the deicing operation is performed by flowing the refrigerant to defrost, it is possible to prevent damage to the functional parts such as the refrigerant pipe and the expansion valve due to the freezing of the refrigerant pipe on the heat source side heat exchanger side, and Generation of noise due to icing of the refrigerant pipe on the side heat exchanger side can be prevented in advance.

  Further, when the icing conditions of the refrigerant pipe on the heat source side heat exchanger side are met by the time measuring means, the unit time is measured for a predetermined unit time, and the addition value determining means determines the refrigerant pipe on the heat source side heat exchanger side from the operating state of the compressor. Estimating the circulating flow rate of the flowing refrigerant, and taking into account the amount of heat absorbed from the surroundings by the refrigerant piping on the heat source side heat exchanger side from the circulating flow rate of the refrigerant, according to the operating state of the compressor every predetermined unit time Determine the addition value. Then, the addition value determined by the addition value determination means is integrated by the integration means, and the icing determination means, when the integrated value in the integration means reaches a preset value, the refrigerant pipe on the heat source side heat exchanger side is frozen. Therefore, the heat source side heat exchanger side can be used more accurately by using an added value that takes into account the operating state of the compressor that affects the ice stacking speed of the refrigerant piping on the heat source side heat exchanger side. It is possible to estimate the ice stacking degree of the refrigerant pipe, and to perform the ice-breaking operation with high accuracy at the necessary timing.

  According to the fourth aspect of the present invention, instead of the refrigerant temperature detecting means, the underground temperature detecting means for detecting the temperature of the heat medium flowing out from the heat source side heat exchanger and flowing into the underground heat exchanger is provided, and the heat source By detecting the temperature of the heat medium flowing out from the heat source side heat exchanger, which is a temperature approximate to the refrigerant temperature of the side heat exchanger, the heat source side heat exchanger is detected from the temperature of the heat medium detected by the underground temperature detecting means. Side refrigerant temperature can be estimated, and the determination of icing of the refrigerant piping on the heat source side heat exchanger side can be made reliably.

1 is a schematic configuration diagram of a first embodiment of the present invention. The principal part block diagram of the 1st Embodiment. The flowchart which shows the operation | movement at the time of ice-melting driving | operation of the 1st embodiment. The principal part block diagram of 2nd Embodiment of this invention. The flowchart which shows the operation | movement at the time of ice-melting operation | movement of the said 2nd Embodiment. The principal part block diagram of 3rd Embodiment of this invention. The flowchart which shows the operation | movement at the time of ice-melting driving | operation of the 3rd embodiment. The other heat pump circuit schematic in the 1st-3rd embodiment of this invention. FIG. 5 is still another heat pump circuit schematic diagram in the first to third embodiments of the present invention. The other schematic block diagram in the 1st-3rd embodiment of this invention. The schematic block diagram of the conventional geothermal heat pump apparatus.

Next, a geothermal heat pump device according to a first embodiment of the present invention will be described with reference to FIGS. 1 and 2.
As shown in FIG. 1, the geothermal heat pump device of the present embodiment is roughly composed of a heat pump unit 1, a geothermal heat exchange unit 2, and a load heat exchange unit 3.

  The heat pump unit 1 circulates a variable capacity compressor 4 for compressing refrigerant and a high-temperature refrigerant discharged from the compressor 4 to exchange heat between the high-temperature refrigerant and the load-side heat medium of the load heat exchange unit 3. A load-side heat exchanger 5 as a condenser to be performed, an expansion valve 6 as a decompression means for decompressing the refrigerant flowing out from the load-side heat exchanger 5, and a decompressed low-temperature refrigerant from the expansion valve 6 are circulated. And a heat source side heat exchanger 7 as an evaporator for exchanging heat with the heat medium on the heat source side of the underground heat exchanging section 2, and these are connected in a ring shape with a refrigerant pipe 8 to form a heat pump circuit 9. It is what. In addition, as a refrigerant | coolant of the heat pump unit 1, arbitrary refrigerant | coolants, such as a carbon dioxide refrigerant | coolant and a HFC refrigerant | coolant, can be used. Further, 10 is provided in the refrigerant pipe 8 on the heat source side heat exchanger 7 side from the expansion valve 6 to the compressor 4, that is, the refrigerant pipe 8 on the low pressure side, and the surface temperature or the low pressure side of the refrigerant pipe 8 on the low pressure side. Reference numeral 11 denotes a refrigerant temperature sensor as refrigerant temperature detection means for detecting the temperature of the refrigerant flowing through the refrigerant pipe 8, and reference numeral 11 denotes an outside air temperature sensor as outside air temperature detection means for detecting the outside air temperature. Here, the outside air temperature is an expression including the outside air temperature outside the heat pump unit 1 and the ambient temperature inside the heat pump unit 1.

  The underground heat exchanger 2 includes a heat source side heat exchanger 7 and a plurality of underground heat exchangers 12 embedded in the ground G as heat sources for heating the refrigerant of the heat source side heat exchanger 7 and connected in parallel to each other. And a ground heat circulation circuit 14 that connects the heat source side heat exchanger 7 and the ground heat exchanger 12 in a ring shape with a heat medium pipe 13, and an antifreeze that is a heat medium circulates in the ground heat circulation circuit 14. And a geothermal circulation pump 15 having a variable rotation speed.

  Here, in the underground heat exchanging section 2, when performing the load operation described later, the underground heat exchanger 12 collects the underground heat from the ground G, and the heat medium having the heat is the underground heat. The heat is supplied to the heat source side heat exchanger 7 by the circulation pump 15. Then, the refrigerant and the heat medium flow oppositely in the heat source side heat exchanger 7 to perform heat exchange, and the underground heat collected by the underground heat exchanger 12 is transferred to the refrigerant side of the heat pump unit 1. The heat source side heat exchanger 7 is pumped up and functions as an evaporator.

  The load heat exchanging unit 3 circulates through a load side heat exchanger 5 that applies heat to the load side, a load terminal 16 such as a floor heating panel that heats the air-conditioned space, and the load side heat exchanger 5 and the load terminal 16. A load-side circulation circuit 17 that is connected in an annular manner, a load-side circulation pump 18 that circulates the circulating fluid for heating in the load-side circulation circuit 17, and a load-side circulation circuit 17 that branches for each load terminal 16. A thermal valve 19 (19a, 19b) for controlling the supply of the circulating fluid for heating to the load terminal 16 by opening and closing is provided. Reference numeral 20 denotes a load forward temperature sensor that is provided in the load-side circulation circuit 17 and detects the temperature of the circulating fluid for heating flowing into the load terminal 16 from the load-side heat exchanger 5.

  A remote control (not shown) is installed in each air-conditioned space heated by the load terminal 16. When the remote controller instructs to heat the air-conditioned space, the compressor 4 and the underground heat are provided. As the driving of the circulation pump 15 and the load side circulation pump 18 is started, the heat source side heat exchanger 7 functions as an evaporator, and the load side heat exchanger 5 functions as a condenser to heat the load side. The heating operation is performed. During the heating operation, in the load-side heat exchanger 5, the refrigerant and the circulating fluid for heating flow to face each other to exchange heat, and the circulating fluid for heating heated in the load-side heat exchanger 5 The air-conditioned space that is sent to the load terminal 16 through the valve 19 and receives an instruction from the remote controller is heated.

  21 receives the input of the refrigerant temperature sensor 10, the outside air temperature sensor 11, the load going temperature sensor 20, and the signal from the remote controller, and the compressor 4, the expansion valve 6, the underground heat circulation pump 15, and the load side circulation pump 18 It is a control means which has the microcomputer which controls the drive of each actuator.

  The control means 21 detects whether or not the refrigerant pipe 8 on the heat source side heat exchanger 7 side is frozen during the heating operation, and the refrigerant temperature sensor 10 detects whether or not the refrigerant temperature sensor 10 is in the heating operation. The icing condition determining means 23 for determining whether or not an icing condition that the refrigerant temperature is equal to or lower than zero degrees and the outside air temperature detected by the outside air temperature sensor 11 is higher than the refrigerant temperature detected by the refrigerant temperature sensor 10 is satisfied; During operation, a predetermined unit time is counted when it is detected that the refrigerant temperature detected by the refrigerant temperature sensor 10 is equal to or lower than zero degrees and the outside air temperature detected by the outside air temperature sensor 11 is higher than the refrigerant temperature detected by the refrigerant temperature sensor 10. Temperature difference between the refrigerant temperature detected by the refrigerant temperature sensor 10 and the outside air temperature detected by the outside air temperature sensor 11 for each predetermined unit time counted by the timer means 24. A first addition value determining means 25 for determining a corresponding addition value, a first integration means 26 for integrating the addition value determined by the first addition value determining means 25, and a de-icing operation to be described later by interrupting the heating operation. And a first storage means 27 for storing a first set value as a reference for starting. The first set value is a value derived and set in advance by performing a test or the like.

  Here, the icing determination means 22 compares the accumulated value accumulated by the first accumulation means 26 with the first set value stored by the first storage means 27 during the heating operation, and the accumulated value is the first value. When the set value is reached, the refrigerant pipe 8 on the heat source side heat exchanger 7 side from the expansion valve 6 to the compressor 4 is frozen, that is, the surface of the refrigerant pipe 8 on the heat source side heat exchanger 7 side. If the icing determination means 22 determines that the refrigerant pipe 8 on the heat source side heat exchanger 7 side is icing, the control means 21 is connected to the underground heat circulation pump. 15 and the load-side circulation pump 18 are stopped, the heating operation is temporarily interrupted, the opening degree of the expansion valve 6 is fully opened or larger than that during the heating operation, and the high-temperature refrigerant discharged from the compressor 4 is exchanged on the heat source side. Refrigerant pipe 8 on the heat source side heat exchanger 7 side after flowing into the refrigerant pipe 8 on the side of the heat exchanger 7 The ice was laminated on the surface and performs thawing operation to thaw. Note that the ice-removal operation is performed for a certain time, and this certain time is obtained by setting in advance a time necessary for melting the ice in the refrigerant pipe 8 on the heat source side heat exchanger 7 side by a test or the like.

  The first addition value determining means 25 determines an addition value corresponding to the temperature difference between the refrigerant temperature detected by the refrigerant temperature sensor 10 and the outside air temperature detected by the outside air temperature sensor 11. , A numerical value as a measure of the thickness of ice stacked on the refrigerant pipe 8 on the heat source side heat exchanger 7 side per predetermined unit time, detected by the refrigerant temperature sensor 10 and the outside air temperature sensor 11 The larger the temperature difference from the outside air temperature, the larger the added value is determined. This is because the larger the temperature difference is, the faster the ice is stacked on the surface of the refrigerant pipe 8 on the heat source side heat exchanger 7 side. For this reason, the first added value determining means 25 stores in advance a data table or the like in which the added value is associated with each temperature difference so that the larger added value is determined as the temperature difference is larger.

Next, the operation of the ice-melting operation during the heating operation of the first embodiment shown in FIGS. 1 and 2 will be described based on the flowchart shown in FIG.
When the load terminal 16 instructs the heating of the air-conditioned space by the remote controller, the control means 21 starts driving the compressor 4, the geothermal circulation pump 15, and the load-side circulation pump 18, and the heating operation is started. Is done. Here, at the start of the heating operation, the underground heat circulation pump 15 starts to be driven at a preset constant rotation speed. When the heating operation is started, the load-side heat exchanger 5 exchanges heat between the circulating fluid for heating circulated by the load-side circulation pump 18 and the high-temperature and high-pressure refrigerant discharged from the compressor 4, and is heated. The circulating fluid for use is supplied to the load terminal 16 to heat the air-conditioned space, and in the heat source side heat exchanger 7, it is circulated by the underground heat circulation pump 15 and collects the underground heat through the underground heat exchanger 12. The heat medium and the low-temperature and low-pressure refrigerant discharged from the expansion valve 6 are heat-exchanged, and the refrigerant is heated and evaporated by underground heat.

  During the heating operation, the icing condition determination means 23 determines whether the refrigerant temperature detected by the refrigerant temperature sensor 10 is equal to or lower than zero degrees and the outside air temperature detected by the outside air temperature sensor 11 is higher than the refrigerant temperature detected by the refrigerant temperature sensor 10. In other words, it is determined whether or not the icing condition is satisfied (step S1), and if it is determined that the icing condition is satisfied, the time measuring unit 24 starts measuring a predetermined unit time, for example, 1 hour, It is determined whether or not the unit time has elapsed (step S2), and if it is determined that the predetermined unit time has elapsed, the first addition value determining means 25 detects the refrigerant temperature and the outside air temperature detected by the refrigerant temperature sensor 10 at that time. The temperature difference (= outside air temperature−refrigerant temperature) is calculated with reference to the outside air temperature detected by the sensor 11, an added value corresponding to the temperature difference is determined (step S 3), and the first integrating means 6 integrates the addition value determined by the first addition value determination means 25 (step S4), and the icing determination means 22 is stored in the first storage means 27 with the integration value integrated by the first integration means 26. The first set value is compared, and it is determined whether or not the integrated value has reached the first set value (step S5). When it is determined that the integrated value has not reached the first set value, The process returns to step S1.

  Then, the processes from step S1 to step S5 are repeated until the integrated value of the first integrating means 26 reaches the first set value stored in the first storage means 27. In the process of step S5, the icing determination means 22 is repeated. However, when it is determined that the integrated value of the first integrating means 26 has reached the first set value stored in the first storage means 27, the control means 21 causes the geothermal circulation pump 15 and the load-side circulation pump 18 to be turned on. The heating operation is stopped, the heating operation is temporarily interrupted, the opening degree of the expansion valve 6 is fully opened, for example, and the high-temperature refrigerant discharged from the compressor 4 flows into the refrigerant pipe 8 on the heat source side heat exchanger 7 side to heat the heat source side heat. The de-icing operation for de-icing the ice stacked on the surface of the refrigerant pipe 8 on the exchanger 7 side is started (step S6).

  In step S6, the control means 21 determines whether or not a certain time, for example, 5 minutes has elapsed when the ice-breaking operation is started (step S7). If it is determined that the certain time has elapsed, the ice-breaking operation is terminated. (Step S8) When the ice melting operation is completed, the integrated value of the first integrating means 26 is cleared to zero, and the driving of the geothermal circulation pump 15 and the load-side circulation pump 18 is started to resume the heating operation. Is.

  On the other hand, if it is determined in step S1 that the icing condition determining means 23 does not satisfy the icing condition, the first integrating means 26 holds and stores the integrated value integrated so far (step S9), and again in step S1. In the middle of repeating the processing from step S1 to step S5 until the integrated value of the first integrating means 26 reaches the first set value stored in the first storage means 27. Even when it is determined in step S1 that the icing condition determining means 23 does not satisfy the icing condition, the first integrating means 26 holds and stores the integrated value accumulated so far in step S9, and again in step S1. Return to processing.

  When the heating operation is stopped, the first integrating means 26 holds and stores the integrated value accumulated so far, and when the heating operation is started again, the first integrated means 26 starts from the integrated value held and stored in the first integrating means 26. Accumulation starts.

  In the deicing operation during the heating operation described above, when the icing determination means 22 determines that the refrigerant pipe 8 on the heat source side heat exchanger 7 side is frozen during the heating operation, the deicing operation is performed. Therefore, it is possible to prevent damage to functional components such as the refrigerant pipe 8 and the expansion valve 6 due to freezing, and to prevent generation of noise due to freezing.

  In step S2, a predetermined unit time is counted when the icing conditions of the refrigerant pipe 8 on the heat source side heat exchanger 7 side are met by the time counting unit 24. In step S3, the first addition value determining unit 25 An addition value corresponding to the temperature difference between the refrigerant temperature and the outside air temperature is determined every predetermined unit time, and the addition value determined by the first addition value determination unit 25 is integrated by the first integration unit 26 in step S4. In step S5, when the icing determination means 22 determines that the integrated value in the first integrating means 26 has reached the preset first set value, the refrigerant pipe 8 on the heat source side heat exchanger 7 side is frozen. By using the addition value considering the temperature difference between the refrigerant temperature and the outside air temperature that affects the ice stacking speed of the refrigerant pipe 8 on the heat source side heat exchanger 7 side, the heat source is more accurately determined. Refrigerant piping on the side heat exchanger 7 side It is possible to estimate the degree of ice stacking of the ice, without performing unnecessary ice-breaking operation, and at a necessary timing before ice is excessively stacked on the surface of the refrigerant pipe 8 on the heat source side heat exchanger 7 side. The ice-breaking operation can be performed with high accuracy. Further, by not performing useless ice-melting operation, the heating output can be stabilized, and the decrease in COP can be suppressed.

  In the present embodiment, the predetermined unit time in step S2 is 1 hour. However, the predetermined unit time may be 2 hours or 5 hours, or may be 1 minute or 1 second. As the predetermined unit time is set shorter, the accuracy of estimating the ice stacking degree of the refrigerant pipe 8 of the heat source side heat exchanger 7 increases.

  In step S3, the first addition value determining means 25 refers to the refrigerant temperature detected by the refrigerant temperature sensor 10 and the outside air temperature detected by the outside air temperature sensor 11 when a predetermined unit time has elapsed, and the temperature is detected. The difference (= outside air temperature−refrigerant temperature) is calculated, and an addition value corresponding to the calculated temperature difference is determined. When the icing condition is satisfied in step S1, the refrigerant temperature and the outside air temperature are referred to. Then, the temperature difference is calculated, the temperature difference is calculated with reference to the refrigerant temperature and the outside air temperature when a predetermined unit time has elapsed, and the average of the calculated temperature differences is calculated. An addition value corresponding to the difference may be used as an addition value integrated in the first integration means 26.

  In addition, when the first addition value determining means 25 refers to the refrigerant temperature detected by the refrigerant temperature sensor 10 and the outside air temperature detected by the outside air temperature sensor 11 when a predetermined unit time has elapsed in step S3, the refrigerant When the relationship between the temperature and the outside air temperature is, for example, the refrigerant temperature is −1 ° C., the outside air temperature is −2 ° C., and the temperature difference calculated by the outside air temperature−the refrigerant temperature is temperature difference ≦ 0, the heat source The addition value may be determined as 0 on the assumption that the ice stack of the refrigerant pipe 8 on the side heat exchanger 7 side is not affected, and 0 may be integrated by the first integration means 26 in the step S4. In addition, when the first addition value determining means 25 refers to the refrigerant temperature detected by the refrigerant temperature sensor 10 and the outside air temperature detected by the outside air temperature sensor 11 when a predetermined unit time has elapsed, the refrigerant temperature and the outside air temperature are calculated. Even if the temperature difference is equal to or less than 0, for example, When the icing condition is established in step S1, the refrigerant temperature is -1 ° C, the outside air temperature is 1 ° C, the temperature difference is 2 ° C, and when a predetermined unit time elapses, the refrigerant temperature is -1 ° C and the outside air temperature is -2 ° C, when the temperature difference is -1 ° C, take the average of the calculated temperature differences, and if the average temperature difference = (2-1) / 2 = 0.5 is greater than 0, average An addition value corresponding to the temperature difference may be determined, and the addition value may be integrated by the first integration means 26 in step S4.

  In step S7, when the control means 21 determines that a predetermined time has elapsed, the ice-breaking operation is terminated in step S8. When the detected temperature detected by the refrigerant temperature sensor 10 reaches a predetermined temperature that is previously derived and set by a test or the like, the ice-breaking operation may be terminated. When the refrigerant temperature sensor 10 detects the surface temperature of the refrigerant pipe 8 on the heat source side heat exchanger 7 side, ice is stretched on the low-pressure side refrigerant pipe 8 during the ice-breaking operation. This is because the detected temperature detected by the refrigerant temperature sensor 10 does not rise so much and the detected temperature detected by the refrigerant temperature sensor 10 gradually increases as the ice in the refrigerant pipe 8 on the low-pressure side melts. If the predetermined temperature at which the ice operation is finished is derived and set by a test or the like in advance, the ice removal operation can be completed without the ice remaining on the surface of the refrigerant pipe 8 on the low pressure side.

  Next, a second embodiment of the present invention shown in FIG. 1 and FIG. 4 will be described. In this embodiment, the same parts as those of the first embodiment described above are denoted by the same reference numerals, and a part of the description will be given. Omitted and the different configuration and operation will be described. Numeral 28 detects the operating state of the compressor 4, that is, the driving frequency or driving current value of the compressor 4, and the second is detected according to the detected value indicating the operating state. 1 is a correction means for correcting the addition value determined by the addition value determination means 25. In the present embodiment, the first integration means 26 integrates the addition value corrected by the correction means 28.

  The correction unit 28 multiplies the addition value determined by the first addition value determination unit 25 by a correction coefficient corresponding to a detection value such as a drive frequency or a drive current value indicating the operation state of the compressor 4. Thus, the larger the detected value of the compressor 4 is, the larger the corrected value is corrected. This is because as the detected value of the compressor 4 is larger, the circulating flow rate of the refrigerant circulating in the heat pump circuit 9 is increased, and accordingly, the circulating flow rate of the refrigerant flowing through the refrigerant pipe 8 on the heat source side heat exchanger 7 side is also increased. This is because the amount of heat absorbed by the refrigerant pipe 8 on the heat source side heat exchanger 7 side from the surroundings increases, and the speed at which ice is stacked on the surface of the refrigerant pipe 8 on the heat source side heat exchanger 7 side increases. Therefore, the correction means 28 is associated with a correction coefficient for each detected value so that the larger the detected value of the compressor 4 is, the more the added value determined by the first added value determining means 25 is corrected. A data table or the like is stored in advance. Note that the correction coefficient may include not only a value to be corrected to increase the added value but also a value to be corrected to decrease the added value.

Next, the operation of the ice-melting operation during the heating operation of the second embodiment shown in FIGS. 1 and 4 will be described based on the flowchart shown in FIG.
When the load terminal 16 instructs the heating of the air-conditioned space by the remote controller, the control means 21 starts driving the compressor 4, the geothermal circulation pump 15, and the load-side circulation pump 18, and the heating operation is started. Is done. Here, at the start of the heating operation, the underground heat circulation pump 15 starts to be driven at a preset constant rotation speed. When the heating operation is started, the load-side heat exchanger 5 exchanges heat between the circulating fluid for heating circulated by the load-side circulation pump 18 and the high-temperature and high-pressure refrigerant discharged from the compressor 4, and is heated. The circulating fluid for use is supplied to the load terminal 16 to heat the air-conditioned space, and in the heat source side heat exchanger 7, it is circulated by the underground heat circulation pump 15 and collects the underground heat through the underground heat exchanger 12. The heat medium and the low-temperature and low-pressure refrigerant discharged from the expansion valve 6 are heat-exchanged, and the refrigerant is heated and evaporated by underground heat.

  During the heating operation, the icing condition determination means 23 determines whether the refrigerant temperature detected by the refrigerant temperature sensor 10 is equal to or lower than zero degrees and the outside air temperature detected by the outside air temperature sensor 11 is higher than the refrigerant temperature detected by the refrigerant temperature sensor 10. In other words, it is determined whether or not the icing condition is satisfied (step S10). When it is determined that the icing condition is satisfied, the time measuring unit 24 starts measuring a predetermined unit time, for example, 1 hour. It is determined whether or not the unit time has elapsed (step S11), and if it is determined that the predetermined unit time has elapsed, the first addition value determining means 25 detects the refrigerant temperature and the outside air temperature detected by the refrigerant temperature sensor 10 at that time. The temperature difference (= outside air temperature−refrigerant temperature) is calculated with reference to the outside air temperature detected by the sensor 11, and an addition value corresponding to the temperature difference is determined (step S12). 28 detects the operation state of the compressor 4 at that time, for example, the drive frequency of the compressor 4, and multiplies the addition value determined by the first addition value determination means 25 by the correction coefficient corresponding to the detected value to obtain the addition value. Correction (step S13), the first integration means 26 integrates the addition value corrected by the correction means 28 (step S14), and the icing determination means 22 calculates the integrated value integrated by the first integration means 26 and the first integration value. The first set value stored in the first storage means 27 is compared to determine whether or not the integrated value has reached the first set value (step S15), and the integrated value has reached the first set value. If it is determined that there is not, the process returns to step S10 again.

  Then, the processes from step S10 to step S15 are repeated until the integrated value of the first integrating means 26 reaches the first set value stored in the first storage means 27, and in the process of step S15, the icing determination means 22 However, when it is determined that the integrated value of the first integrating means 26 has reached the first set value stored in the first storage means 27, the control means 21 causes the geothermal circulation pump 15 and the load-side circulation pump 18 to be turned on. The heating operation is stopped, the heating operation is temporarily interrupted, the opening degree of the expansion valve 6 is fully opened, for example, and the high-temperature refrigerant discharged from the compressor 4 flows into the refrigerant pipe 8 on the heat source side heat exchanger 7 side to heat the heat source side heat. The de-icing operation for de-icing the ice stacked on the surface of the refrigerant pipe 8 on the exchanger 7 side is started (step S16).

  In step S16, the control means 21 determines whether or not a certain time, for example, 5 minutes has elapsed when the ice-breaking operation is started (step S17). If it is determined that the certain time has elapsed, the ice-breaking operation is terminated. (Step S18) When the ice melting operation is completed, the integrated value of the first integrating means 26 is cleared to zero, and the driving of the geothermal circulation pump 15 and the load-side circulation pump 18 is started to resume the heating operation. Is.

  On the other hand, if it is determined in step S10 that the icing condition determining means 23 does not satisfy the icing condition, the first integrating means 26 holds and stores the integrated value accumulated so far (step S19), and again in step S10. In the middle of repeatedly performing the processing from step S10 to step S15 until the integrated value of the first integrating means 26 reaches the first set value stored in the first storage means 27. Even if it is determined in step S10 that the icing condition determining means 23 does not hold the icing condition, the first integrating means 26 holds and stores the integrated value accumulated so far in step S19, and again in step S10. Return to processing.

  When the heating operation is stopped, the first integrating means 26 holds and stores the integrated value accumulated so far, and when the heating operation is started again, the first integrated means 26 starts from the integrated value held and stored in the first integrating means 26. Accumulation starts.

  In the deicing operation during the heating operation described above, in the characteristic part of the present embodiment, in step S13, the correction means 28 determines the refrigerant on the heat source side heat exchanger 7 side from the operating state of the compressor 4. The first addition value determination means 25 estimates the circulation flow rate of the refrigerant flowing through the pipe 8 and takes into account the amount of heat absorbed by the refrigerant pipe 8 on the heat source side heat exchanger 7 side from the surroundings based on the circulation flow rate of the refrigerant. In addition to the determined addition value, in step S14, the first integration means 26 integrates the addition value corrected by the correction means 28, so that the ice in the refrigerant pipe 8 on the heat source side heat exchanger 7 side can be further accurately detected. It is possible to estimate the degree of lamination.

  Next, a third embodiment of the present invention shown in FIGS. 1 and 6 will be described. In this embodiment, the same parts as those of the first embodiment described above are denoted by the same reference numerals, and a part of the description will be given. Omitted and different configurations and operations will be described.

  The control means 21 detects whether or not the refrigerant pipe 8 on the heat source side heat exchanger 7 side is frozen during the heating operation, and the refrigerant temperature sensor 10 detects whether or not the refrigerant temperature sensor 10 is in the heating operation. The icing condition determining means 23 for determining whether or not an icing condition that the refrigerant temperature is equal to or lower than zero degrees and the outside air temperature detected by the outside air temperature sensor 11 is higher than the refrigerant temperature detected by the refrigerant temperature sensor 10 is satisfied; During operation, a predetermined unit time is counted when it is detected that the refrigerant temperature detected by the refrigerant temperature sensor 10 is equal to or lower than zero degrees and the outside air temperature detected by the outside air temperature sensor 11 is higher than the refrigerant temperature detected by the refrigerant temperature sensor 10. The time measuring means 24 and the operating state of the compressor 4, that is, the driving frequency or driving current value of the compressor 4 are detected, and the compressor is measured every predetermined unit time measured by the time measuring means 24. A second addition value determination means 29 for determining an addition value corresponding to the detected value indicating the operating state of the second, a second integration means 30 for integrating the addition value determined by the second addition value determination means 29, and the heating operation. And a second storage means 31 for storing a second set value serving as a reference for interrupting and starting an ice melting operation described later. The second set value is a value that is derived and set by conducting a test or the like in advance.

  Here, the icing determination means 22 compares the accumulated value accumulated by the second accumulation means 30 with the second set value stored by the second storage means 31 during the heating operation, and the accumulated value is the first value. 2 When the set value is reached, the refrigerant pipe 8 on the heat source side heat exchanger 7 side from the expansion valve 6 to the compressor 4 is frozen, that is, the surface of the refrigerant pipe 8 on the heat source side heat exchanger 7 side. If the icing determination means 22 determines that the refrigerant pipe 8 on the heat source side heat exchanger 7 side is icing, the control means 21 is connected to the underground heat circulation pump. 15 and the load-side circulation pump 18 are stopped, the heating operation is temporarily interrupted, the opening degree of the expansion valve 6 is fully opened or larger than that during the heating operation, and the high-temperature refrigerant discharged from the compressor 4 is exchanged on the heat source side. Refrigerant pipe 8 on the heat source side heat exchanger 7 side after flowing into the refrigerant pipe 8 on the side of the heat exchanger 7 The ice was laminated on the surface and performs thawing operation to thaw. Note that the ice-removal operation is performed for a certain time, and this certain time is obtained by setting in advance a time necessary for melting the ice in the refrigerant pipe 8 on the heat source side heat exchanger 7 side by a test or the like.

  The second addition value determining means 29 determines an addition value corresponding to a detection value such as a drive frequency or a drive current value indicating the operation state of the compressor 4, and this addition value is a predetermined unit time. It is a numerical value as a measure of the thickness of ice stacked on the refrigerant pipe 8 on the heat source side heat exchanger 7 side, and the larger the detected value of the compressor 4, the larger the added value is determined. This is because as the detected value of the compressor 4 is larger, the circulating flow rate of the refrigerant circulating in the heat pump circuit 9 is increased, and accordingly, the circulating flow rate of the refrigerant flowing through the refrigerant pipe 8 on the heat source side heat exchanger 7 side is also increased. This is because the amount of heat absorbed by the refrigerant pipe 8 on the heat source side heat exchanger 7 side from the surroundings increases, and the speed at which ice is stacked on the surface of the refrigerant pipe 8 on the heat source side heat exchanger 7 side increases. Therefore, the second addition value determining means 29 stores in advance a data table or the like in which the addition value is associated with each detection value so that the larger the detection value of the compressor 4 is, the larger the addition value is determined. Is.

Next, the operation of the ice-melting operation during the heating operation of the third embodiment shown in FIGS. 1 and 6 will be described based on the flowchart shown in FIG.
When the load terminal 16 instructs the heating of the air-conditioned space by the remote controller, the control means 21 starts driving the compressor 4, the geothermal circulation pump 15, and the load-side circulation pump 18, and the heating operation is started. Is done. Here, at the start of the heating operation, the underground heat circulation pump 15 starts to be driven at a preset constant rotation speed. When the heating operation is started, the load-side heat exchanger 5 exchanges heat between the circulating fluid for heating circulated by the load-side circulation pump 18 and the high-temperature and high-pressure refrigerant discharged from the compressor 4, and is heated. The circulating fluid for use is supplied to the load terminal 16 to heat the air-conditioned space, and in the heat source side heat exchanger 7, it is circulated by the underground heat circulation pump 15 and collects the underground heat through the underground heat exchanger 12. The heat medium and the low-temperature and low-pressure refrigerant discharged from the expansion valve 6 are heat-exchanged, and the refrigerant is heated and evaporated by underground heat.

  During the heating operation, the icing condition determination means 23 determines whether the refrigerant temperature detected by the refrigerant temperature sensor 10 is equal to or lower than zero degrees and the outside air temperature detected by the outside air temperature sensor 11 is higher than the refrigerant temperature detected by the refrigerant temperature sensor 10. No, that is, whether or not the icing condition is satisfied (step S20). If it is determined that the icing condition is satisfied, the time measuring unit 24 starts measuring a predetermined unit time, for example, 1 hour, It is determined whether or not the unit time has elapsed (step S21), and if it is determined that the predetermined unit time has elapsed, the second addition value determining means 29 determines the operation state of the compressor 4 when the predetermined unit time has elapsed. The detected value, for example, the drive frequency of the compressor 4 is detected, an addition value corresponding to the detected value is determined (step S22), and the second integration means 30 is the addition determined by the second addition value determination means 29 (Step S23), the icing determination means 22 compares the integrated value integrated by the second integrating means 30 with the second set value stored by the second storage means 31, and the integrated value is It is determined whether or not the second set value has been reached (step S24). If it is determined that the integrated value has not reached the second set value, the process returns to step S20 again.

  Then, the process from step S20 to step S24 is repeated until the integrated value of the second integration means 30 reaches the second set value stored in the second storage means 31, and in the process of step S24, the icing determination means 22 However, when it is determined that the integrated value of the second integration means 30 has reached the second set value stored in the second storage means 31, the control means 21 causes the underground heat circulation pump 15 and the load-side circulation pump 18 to The heating operation is stopped, the heating operation is temporarily interrupted, the opening degree of the expansion valve 6 is fully opened, for example, and the high-temperature refrigerant discharged from the compressor 4 flows into the refrigerant pipe 8 on the heat source side heat exchanger 7 side to heat the heat source side heat. The de-icing operation for de-icing the ice stacked on the surface of the refrigerant pipe 8 on the exchanger 7 side is started (step S25).

  In step S25, the control means 21 determines whether or not a certain time, for example, 5 minutes has elapsed when the ice-breaking operation is started (step S26). If it is determined that the certain time has elapsed, the ice-breaking operation is terminated. (Step S27) When the ice melting operation is completed, the integrated value of the second integrating means 30 is cleared to zero, and the driving of the geothermal circulation pump 15 and the load-side circulation pump 18 is started to resume the heating operation. Is.

  On the other hand, if it is determined in step S20 that the icing condition determining means 23 does not satisfy the icing condition, the second integrating means 30 holds and stores the integrated value accumulated so far (step S28), and again in step S20. In the middle of repeatedly performing the processing from step S20 to step S24 until the integrated value of the second integrating means 30 reaches the second set value stored in the second storage means 31. Even if it is determined in step S20 that the icing condition determining means 23 does not hold the icing condition, the second integrating means 30 holds and stores the integrated value accumulated so far in step S28, and again in step S20. Return to processing.

  When the heating operation is stopped, the second integrating means 30 holds and stores the integrated value accumulated so far, and when the heating operation is started again, the second integrating means 30 starts from the integrated value held and stored in the second integrating means 30. Accumulation starts.

  In the deicing operation during the heating operation described above, when the icing determination means 22 determines that the refrigerant pipe 8 on the heat source side heat exchanger 7 side is frozen during the heating operation, the deicing operation is performed. Therefore, it is possible to prevent damage to functional components such as the refrigerant pipe 8 and the expansion valve 6 due to freezing, and to prevent generation of noise due to freezing.

  In step S21, a predetermined unit time is counted when the icing conditions of the refrigerant pipe 8 on the heat source side heat exchanger 7 side are met by the time counting unit 24. In step S22, the second addition value determining unit 29 Then, the circulation flow rate of the refrigerant flowing through the refrigerant pipe 8 on the heat source side heat exchanger 7 side is estimated from the detected value indicating the operation state of the compressor 4, and the refrigerant pipe 8 on the heat source side heat exchanger 7 side is estimated from the circulation flow rate of the refrigerant. In consideration of the amount of heat absorbed from the surroundings, an addition value corresponding to the detected value indicating the operating state of the compressor 4 is determined every predetermined unit time counted by the time measuring means 24. In step S23, the second value is determined. The addition value determined by the second addition value determination unit 29 is integrated by the integration unit 30, and in step S24, the icing determination unit 22 reaches the second set value set in advance by the integration value in the second integration unit 30. Heat source Addition considering the operating state of the compressor 4 that affects the ice stacking speed of the refrigerant pipe 8 on the heat source side heat exchanger 7 side by judging that the refrigerant pipe 8 on the heat exchanger 7 side is frozen. By using the value, it is possible to estimate the ice stacking degree of the refrigerant pipe 8 on the heat source side heat exchanger 7 side more accurately, without performing useless ice-breaking operation, and the heat source side heat exchanger 7 Before the ice is excessively stacked on the surface of the refrigerant pipe 8 on the side, the ice-breaking operation can be accurately performed at a necessary timing. Further, by not performing useless ice-melting operation, the heating output can be stabilized, and the decrease in COP can be suppressed.

  In the present embodiment, the predetermined unit time in step S21 is 1 hour, but the predetermined unit time may be 2 hours or 5 hours, or may be 1 minute or 1 second. As the predetermined unit time is set shorter, the accuracy of estimating the ice stacking degree of the refrigerant pipe 8 of the heat source side heat exchanger 7 increases.

  In step S22, the second addition value determining means 29 detects a detection value indicating the operating state of the compressor 4 when a predetermined unit time has elapsed, for example, the driving frequency of the compressor 4, and uses the detected value as the detection value. The corresponding addition value is determined. When the icing condition is established in step S20, a detection value indicating the operating state of the compressor 4 is detected, and the compressor 4 at the time when a predetermined unit time has elapsed. The detected value indicating the operating state is detected, the average of both detected values is averaged, and the added value corresponding to the average detected value may be added to the second integrating means 30.

  In step S26, when the control means 21 determines that a predetermined time has elapsed, the ice-breaking operation is terminated in step S27. However, the control means 21 is in the ice-breaking operation. When the detected temperature detected by the refrigerant temperature sensor 10 reaches a predetermined temperature that is previously derived and set by a test or the like, the ice-breaking operation may be terminated. When the refrigerant temperature sensor 10 detects the surface temperature of the refrigerant pipe 8 on the heat source side heat exchanger 7 side, ice is stretched on the low-pressure side refrigerant pipe 8 during the ice-breaking operation. This is because the detected temperature detected by the refrigerant temperature sensor 10 does not rise so much and the detected temperature detected by the refrigerant temperature sensor 10 gradually increases as the ice in the refrigerant pipe 8 on the low-pressure side melts. If the predetermined temperature at which the ice operation is finished is derived and set by a test or the like in advance, the ice removal operation can be completed without the ice remaining on the surface of the refrigerant pipe 8 on the low pressure side.

  The present invention is not limited to the first to third embodiments described above. In the first to third embodiments, the expansion valve 6 is fully opened during the ice-breaking operation and the compressor 4 is used. Although the discharged high-temperature refrigerant flows through the heat source side heat exchanger 7, as shown in FIG. 8, the bypass pipe 32 bypassing the load side heat exchanger 5 and the expansion valve 6 in the heat pump circuit 9, and its bypass An on-off valve 33 for opening and closing the pipe 32 is opened, and the on-off valve 33 is opened during the ice-breaking operation so that the high-temperature refrigerant discharged from the compressor 4 flows directly into the heat source side heat exchanger 7 to A high-temperature refrigerant may be allowed to flow through the exchanger 7, and as shown in FIG. 9, the heat pump circuit 9 causes the heat source side heat exchanger 7 to function as an evaporator during heating operation, and load side heat exchange. Function as a condenser, heat the load side, In some cases, the heat source side heat exchanger 7 is made to function as a condenser, and the load side heat exchanger 5 is made to function as an evaporator so that the heat source side is heated so that the heat source side is heated. The four-way valve 34 is switched so that the compressor 7 functions as a condenser, and the high-temperature refrigerant discharged from the compressor 4 is caused to flow directly into the heat source side heat exchanger 7 as shown by the dotted arrows in FIG. A high-temperature refrigerant may be allowed to flow through the side heat exchanger 7.

  The present invention is not limited to the first to third embodiments described above. In the first to third embodiments, a plurality of underground heat exchangers 12 embedded in the ground G are used. Are connected in parallel with each other, but a plurality of underground heat exchangers 12 may be connected in series with each other, and a desired heat collection from the ground G without embedding a plurality of underground heat exchangers 12. If it is possible, only one underground heat exchanger 12 may be embedded.

  In addition, the present invention is not limited to the first to third embodiments described above, and in the first to third embodiments, the room is an air-conditioned space by the load terminal 16 such as a floor heating panel. Although the heating medium circulation type heating operation for heating the vehicle is a load operation, an indoor unit (not shown) having a load-side heat exchanger 5 is provided in a room that is an air-conditioned space. Heating operation in which the discharged high-temperature refrigerant directly exchanges heat with room air and heats the room by blowing air may be used as load operation, and a hot water storage tank (for storing hot water used for hot water supply or the like by the load terminal 16) The heating operation for boiling hot water in the hot water storage tank may be a load operation, and various modifications are possible without departing from the scope of the present invention, and this is not disturbed. .

  Further, the present invention is not limited to the first to third embodiments described above, and in the first to third embodiments, the icing determination means 22 is the refrigerant temperature detected by the refrigerant temperature sensor 10. Based on the above, it is determined whether or not the refrigerant pipe 8 of the heat source side heat exchanger 7 is frozen. As shown in FIG. 17, instead of the refrigerant temperature sensor 10, the heat source side heat exchanger 7 An underground temperature sensor 35 is provided as an underground temperature detecting means for detecting the temperature of the heat medium of the underground heat circulation circuit 14 that flows out and flows into the underground heat exchanger 12. Based on the heat medium temperature detected by the middle temperature sensor 35 and the outside air temperature detected by the outside air temperature sensor 11, it may be determined whether or not the refrigerant pipe 8 of the heat source side heat exchanger 7 is frozen. . This is a temperature in which the temperature of the heat medium flowing out from the heat source side heat exchanger 7 approximates the refrigerant temperature flowing into the heat source side heat exchanger 7, and the refrigerant temperature on the heat source side heat exchanger 7 side from the heat medium temperature. The icing determination means 22 can reliably determine the icing of the refrigerant pipe 8 of the heat source side heat exchanger 7 by using the heat medium temperature detected by the underground temperature sensor 35. It can be done.

DESCRIPTION OF SYMBOLS 4 Compressor 5 Load side heat exchanger 6 Expansion valve 7 Heat source side heat exchanger 8 Refrigerant piping 9 Heat pump circuit 10 Refrigerant temperature sensor 11 Outside air temperature sensor 12 Ground heat exchanger 13 Heat medium piping 14 Ground heat circulation circuit 15 Ground Medium heat circulation pump 22 Freezing determination means 24 Timekeeping means 25 First addition value determination means 26 First integration means 28 Correction means 29 Second addition value determination means 30 Second integration means 35 Underground temperature sensor

Claims (4)

  A compressor, a load-side heat exchanger, a decompression means, a heat pump circuit in which a heat source-side heat exchanger is annularly connected by a refrigerant pipe, an underground heat exchanger embedded in the ground, the underground heat exchanger, A ground heat circulation circuit that is annularly connected to the heat source side heat exchanger with a heat medium pipe, a ground heat circulation pump that circulates the heat medium in the ground heat circulation circuit, and the heat source side heat exchanger side A refrigerant temperature detecting means for detecting the temperature of the refrigerant and an outside air temperature detecting means for detecting the outside air temperature, collecting underground heat by the underground heat exchanger, and using the heat source side heat exchanger as an evaporator In the geothermal heat pump device that performs the load operation that causes the load side heat exchanger to function as a condenser and heats the load side, the refrigerant temperature detected by the refrigerant temperature detecting means during the load operation Less than zero degree and detected by the outside air temperature detecting means Time measuring means for measuring a predetermined unit time when the air temperature is higher than the refrigerant temperature detected by the refrigerant temperature detecting means, the refrigerant temperature detected by the refrigerant temperature detecting means for each predetermined unit time, and the outside air temperature detecting means An addition value determining means for determining an added value according to a temperature difference from the detected outside air temperature, an integrating means for integrating the added value determined by the added value determining means, and an integrated value in the integrating means are preset. When the set value is reached, there is provided icing judgment means for judging that the refrigerant pipe on the heat source side heat exchanger side is frozen, and the refrigerant pipe on the heat source side heat exchanger side is frozen by the icing judgment means. If it is determined that the heat source is in the ground, the ground heat heat pump device is configured to perform a deicing operation in which a high-temperature refrigerant flows through the refrigerant pipe on the heat source side heat exchanger side to perform ice melting.   2. The underground heat pump apparatus according to claim 1, further comprising a correcting unit that detects an operating state of the compressor and corrects the addition value determined by the adding value determining unit according to the operating state, and the integrating unit. Is a geothermal heat pump device that integrates the added values corrected by the correcting means.   A compressor, a load-side heat exchanger, a decompression means, a heat pump circuit in which a heat source-side heat exchanger is annularly connected by a refrigerant pipe, an underground heat exchanger embedded in the ground, the underground heat exchanger, A ground heat circulation circuit that is annularly connected to the heat source side heat exchanger with a heat medium pipe, a ground heat circulation pump that circulates the heat medium in the ground heat circulation circuit, and the heat source side heat exchanger side A refrigerant temperature detecting means for detecting the temperature of the refrigerant and an outside air temperature detecting means for detecting the outside air temperature, collecting underground heat by the underground heat exchanger, and using the heat source side heat exchanger as an evaporator In the geothermal heat pump device that performs the load operation that causes the load side heat exchanger to function as a condenser and heats the load side, the refrigerant temperature detected by the refrigerant temperature detecting means during the load operation Less than zero degree and detected by the outside air temperature detecting means Time measuring means for measuring a predetermined unit time when the air temperature is higher than the refrigerant temperature detected by the refrigerant temperature detecting means, and detecting the operating state of the compressor, and operating the compressor every predetermined unit time An addition value determining means for determining an addition value according to the above, an integration means for integrating the addition value determined by the addition value determination means, and when the integrated value at the integration means reaches a preset set value, the heat source An icing determining means for determining that the refrigerant pipe on the side heat exchanger side is frozen, and when the icing determining means determines that the refrigerant pipe on the heat source side heat exchanger side is frozen, A geothermal heat pump apparatus characterized in that a deicing operation is performed in which a high-temperature refrigerant is allowed to flow through a refrigerant pipe on the heat source side heat exchanger side to perform ice melting.   The underground heat heat pump device according to any one of claims 1 to 3, wherein a heat medium that flows out of the heat source side heat exchanger and flows into the underground heat exchanger instead of the refrigerant temperature detection means. A geothermal heat pump device provided with underground temperature detecting means for detecting temperature.

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