WO2021166040A1

WO2021166040A1 - Refrigeration cycle device

Info

Publication number: WO2021166040A1
Application number: PCT/JP2020/006097
Authority: WO
Inventors: 圭岡本; 寛也石原; 池田　隆
Original assignee: 三菱電機株式会社
Priority date: 2020-02-17
Filing date: 2020-02-17
Publication date: 2021-08-26
Also published as: JP7209892B2; JPWO2021166040A1

Abstract

This refrigeration cycle device (100) is provided with a refrigerant circuit (40) through which a refrigerant is circulated. The refrigerant circuit (40) is constituted by annularly connecting a compressor (5), a first heat exchanger (6), a decompression device (8), and a second heat exchanger (7). The second heat exchanger (7) is configured to exchange heat between a refrigerant and a heating medium. The refrigeration cycle device (100) is further equipped with: a first pressure sensor (3) for detecting the pressure of the heating medium at a heating-medium inlet of the second heat exchanger (7); and a second pressure sensor (4) for detecting the pressure of the heating medium at a heating-medium outlet of the second heat exchanger (7).

Description

Refrigeration cycle equipment

This disclosure relates to a refrigeration cycle device.

An example of a refrigeration cycle device that supplies cold and hot heat is disclosed in, for example, International Publication No. 2016/071977 (Patent Document 1). This refrigeration cycle device is equipped with a water heat exchanger, the average value of the water temperature at the inlet and outlet of the water heat exchanger is higher than the reference value (for example, 4.5 ° C.), and the outlet superheat degree of the water heat exchanger is the reference value (for example). For example, when the temperature is higher than 7.5 ° C.), the antifreeze control is executed. As anti-freezing control, the stop temperature of the compressor is set higher than the currently set stop temperature, or the rotation speed of the water pump is set higher than the currently set rotation speed to increase the flow velocity of water. , Etc. are exemplified.

International Publication No. 2016/071977

When water is used as a heat medium, the refrigeration cycle apparatus proposed in Patent Document 1 described above performs operations such as increasing the flow rate of the pump when the temperature of the heat medium approaches the freezing point to freeze. It is to prevent.

However, since the refrigeration cycle apparatus assumes water as a heat medium, the physical properties of the heat medium are specifically controlled by protection on the premise that the freezing point is 0 ° C. I haven't taken it into consideration. For example, when brine is used as a heat medium, the freezing point differs depending on the type and concentration of each brine. In addition, the concentration of brine changes due to a hygroscopic reaction due to the nature of brine, evaporation of water in the solution, or the like, so that the freezing point also changes. Therefore, it is not easy to set a temperature threshold value for determining whether or not to increase the flow rate. Due to the change in concentration due to moisture absorption or evaporation of brine, problems such as damage to the heat exchanger and pump failure due to freezing of brine may occur.

The refrigeration cycle apparatus of the present disclosure solves the above-mentioned problems and can detect an abnormality in a circuit using a heat medium.

This disclosure relates to a refrigeration cycle device. The refrigeration cycle apparatus includes a refrigerant circuit configured to circulate the refrigerant so as to repeat a compression process, a condensation process, an expansion process, and an evaporation process. The refrigerant circuit includes a heat exchanger configured to exchange heat between the refrigerant and the heat medium. The refrigeration cycle apparatus has a first pressure sensor that detects the pressure of the heat medium in the inlet side flow path of the heat medium of the heat exchanger, and a first pressure sensor that detects the pressure of the heat medium in the outlet side flow path of the heat medium of the heat exchanger. It is further equipped with two pressure sensors.

According to the refrigeration cycle apparatus of the present disclosure, it is possible to detect an abnormality in a circuit using a heat medium by detecting the pressure in the inlet side flow path and the outlet side flow path of the heat exchanger.

It is a figure which shows the structure of the refrigerating cycle apparatus 100 of this embodiment. It is a figure which shows the relationship between the abnormality determination content and the change of the parameter shown in each item. It is a figure which showed the judgment formula for discriminating the abnormality on the load side from the information held by the refrigeration cycle apparatus when the abnormality on the load side occurs. It is a flowchart for demonstrating the procedure for determining the determination content to be notified by a control device 20. It is a figure which shows the structure of the refrigerating cycle apparatus 100A of the 1st modification. It is a figure which shows the structure of the refrigerating cycle apparatus 100B of the 2nd modification.

Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. Hereinafter, a plurality of embodiments will be described, but it is planned from the beginning of the application that the configurations described in the respective embodiments are appropriately combined. The same or corresponding parts in the drawings are designated by the same reference numerals, and the description thereof will not be repeated. In the figure below, the relationship between the sizes of each component may differ from the actual one.

The refrigerating cycle device exemplified in the present embodiment relates to a refrigerating and air-conditioning device, and particularly relates to a refrigerating and air-conditioning device that supplies cold and hot heat to the load side by heating or cooling a liquid medium such as water or brine. ..

FIG. 1 is a diagram showing the configuration of the refrigeration cycle device 100 of the present embodiment. The refrigeration cycle device 100 includes a heat source machine 1, a pump 2, and a load device 30.

A compressor 5, a first heat exchanger 6 which is a heat source side heat exchanger, an expansion valve 8 which is a decompression device, and a second heat exchanger 7 which is a load side heat exchanger are built in the heat source machine 1. There is. In the first heat exchanger 6, heat exchange is performed between the air and the refrigerant. The first heat exchanger 6 is provided with a fan 12 for blowing air. In the second heat exchanger 7, heat exchange is performed between a heat medium such as water or brine and the refrigerant. As the second heat exchanger 7, a plate heat exchanger can be used.

The compressor 5, the first heat exchanger 6, the expansion valve 8, and the second heat exchanger 7 are connected in an annular shape as shown to form a refrigerant circuit in which the refrigerant circulates.

The compressor 5 compresses the refrigerant. The compressor 5 is, for example, an inverter compressor controlled by an inverter, and the compression capacity per hour can be changed. However, the compressor 5 may be a constant speed type compressor.

The first heat exchanger 6 exchanges heat with air for the refrigerant, and functions as a heat source side heat exchanger. However, the first heat exchanger 6 may be another heat exchanger in which heat exchange is performed between a heat medium other than air and the refrigerant.

The expansion valve 8 expands the refrigerant. The expansion valve 8 may be formed of an electronic expansion valve or the like whose opening degree can be adjusted, but may be a capillary tube or the like.

The second heat exchanger 7 exchanges heat between the refrigerant and the heat medium, and functions as a load-side heat exchanger. As the second heat exchanger 7, a heat exchanger such as a shell-and-tube heat exchanger other than the plate heat exchanger may be used.

Pump 2 is a power source that circulates a heat medium in the load side flow path. Although the pump 2 is provided outside the heat source machine 1 and connected to the heat source machine 1 in FIG. 1, it may be built in the heat source machine 1.

The refrigeration cycle device 100 further includes a control device 20 that controls a compressor 5, a fan 12, an expansion valve 8, and a pump 2.

The control device 20 includes a CPU (Central Processing Unit) 21 and a memory 22. The memory 22 includes, for example, a ROM (Read Only Memory), a RAM (Random Access Memory), and a flash memory. The flash memory stores the operating system, application programs, and various types of data.

The CPU 21 controls the overall operation of the refrigeration cycle device 100. The control device 20 shown in FIG. 1 is realized by the CPU 21 executing the operating system and the application program stored in the memory 22. When executing the application program, various data stored in the memory 22 are referred to.

When the second heat exchanger 7 is separated from the heat source machine 1 as a repeater or the like, the control device 20 may be divided into a plurality of control units. In this case, each of the plurality of control units includes a CPU and a memory. In such a case, a plurality of CPUs cooperate to perform overall control of the refrigeration cycle device 100.

The refrigeration cycle device 100 includes a pressure sensor 3 for detecting the pressure of the heat medium at the heat medium inlet of the second heat exchanger 7, which is a load side heat exchanger, and a heat medium at the heat medium outlet of the second heat exchanger 7. A pressure sensor 4 for detecting the pressure and a current sensor 11 for detecting the current of the pump 2 are further provided.

The heat medium is cooled by the second heat exchanger 7 and supplied to the load device 30. The control device 20 determines an abnormality in the load-side circuit by a discriminant based on the outputs of the

pressure sensors

3 and 4, and reports the abnormality when the abnormality is detected. By reporting an abnormality in the load-side circuit, appropriate circuit protection can be performed even if the physical properties of the heat medium change.

Next, the abnormality notification of the load-side device in the refrigeration cycle device 100 will be described with reference to FIGS. 1 to 3.

FIG. 2 is a diagram showing the relationship between the abnormality determination content and the change in the parameters shown in each item. The contents of the abnormality judgment are (1) increase in brine flow rate, (2) decrease in brine concentration, (3) increase in brine concentration, (4) blockage of heat exchanger flow path, (5) blockage of brine piping, and (6) decrease in brine flow rate. , And 6 types. FIG. 2 shows how the parameters shown in each item change when these abnormalities occur. In FIG. 2, the portion surrounded by the double frame is used for classifying the abnormality determination content in the present embodiment.

FIG. 3 is a diagram showing a determination formula for discriminating an abnormality on the load side from the information held by the refrigeration cycle device when an abnormality on the load side occurs. FIG. 3 shows an example in which the heat medium is brine.

Abnormalities on the load side include (1) increase in brine flow rate, (2) decrease in brine concentration, (3) increase in brine concentration, (4) blockage of heat exchanger flow path, (5) blockage of brine piping, and (6) brine. The decrease in flow rate is listed in order. In the following, the pump 2 that feeds brine is assumed to operate at a constant speed.

The reporting conditions for each abnormality determination content shown in FIG. 3 are shown below.
(1) Increase in brine flow rate The control device 20 issues an increase in brine flow rate when the following conditions A and B are satisfied.

[A: Increased cooling capacity]
When the brine flow rate increases, the heat exchange efficiency between the refrigerant and the heat medium is improved. When the heat exchange efficiency is improved, even if the temperature difference between the refrigerant and the brine is small, the same amount of heat as before the heat exchange efficiency is improved can be exchanged. Therefore, in a chiller or a heat pump that performs "constant control of superheat degree (SH)", the evaporation temperature of the refrigerant can be raised, so that the cooling capacity is increased.

Here, "SH constant control" means that the expansion valve 8 is operated to control the degree of superheat of the intake refrigerant in order to prevent liquid backing due to a decrease in the degree of superheat of the intake refrigerant and to prevent a decrease in capacity due to an excessive degree of overheat of the intake refrigerant. It is a control that keeps the set value.

The control device 20 stores in advance the cooling capacity Qurem for each brine cooling capacity and the compressor frequency Hzrem in the steady state. Then, the control device 20 confirms whether the current increase width Qc (= GrΔH) of the cooling capacity is Qc> Qrem, or the frequency Hz after deceleration of the compressor frequency is Hz <Hzrem. Depending on whether or not this determination formula 1 is satisfied, the control device 20 determines whether or not the condition of (A: increase in cooling capacity) is satisfied.

[B: Increased pressure loss]
When the brine flow rate increases, the pressure loss ΔP in the second heat exchanger 7 increases. The pressure loss ΔP is obtained from the difference in pressure detected by the

pressure sensors

3 and 4. The control device 20 stores the pressure loss ΔPrem in the steady state in advance, and when the pressure loss ΔP obtained from the current measured value is higher than the pressure loss ΔPrem, the condition (B: pressure loss increase) is satisfied. Then judge.

(2) Decrease in brine concentration The control device 20 issues a decrease in brine concentration when the above condition A and the following condition C are satisfied.

[C: Pressure loss reduction]
When the brine concentration decreases, the viscosity of the brine generally decreases, so that the pressure loss ΔP in the second heat exchanger 7 decreases. The control device 20 determines that the condition (C: reduction in pressure loss) is satisfied when the current measured value of the pressure loss ΔP is lower than the pressure loss ΔPrem in the steady state.

(3) Increase in brine concentration or (4) Blockage of flow path of heat exchanger When the following conditions D, E, and F are satisfied, the control device 20 notifies that the concentration of brine is increased or the flow path of the heat exchanger is blocked. do.

[D: Decreased cooling capacity]
When the brine concentration increases, the thermal conductivity generally decreases and the heat exchange efficiency decreases. When the heat exchange efficiency decreases, the degree of superheat of the intake refrigerant decreases. In a chiller or a heat pump that performs constant SH control, it is necessary to reduce the opening degree of the expansion valve 8 to lower the evaporation temperature as a countermeasure. In this case, the cooling capacity is reduced.

Further, when the flow path of the second heat exchanger 7 is blocked, the heat exchange efficiency of the second heat exchanger 7 decreases. In a chiller or a heat pump that constantly controls SH when the heat exchange efficiency decreases, it is necessary to reduce the opening degree of the expansion valve 8 to reduce the evaporation temperature. In this case, the cooling capacity is reduced.

The control device 20 stores in advance the outside air temperature, the cooling capacity Qurem for each brine cooling capacity, and the compressor frequency Hzrem in the steady state. The control device 20 determines that the condition (D: decrease in cooling capacity) is satisfied when the current decrease in cooling capacity Qc (= GrΔH) <Qrem or the acceleration Hz of the compressor frequency> Hzrem is satisfied. ..

[E: Increased pressure loss]
When the brine concentration increases, the viscosity generally increases, so that the pressure loss ΔP in the second heat exchanger 7 increases. Further, when the flow path of the second heat exchanger 7 is blocked, the flow path through which the heat medium flows becomes narrow, so that the pressure loss in the second heat exchanger 7 increases. The control device 20 determines that the condition (E: pressure loss increase) is satisfied when the pressure loss ΔP obtained from the current measured value is higher than the pressure loss ΔPrem in the steady state.

[F: ΔP measured value> ΔPc (calculated value)]
The density, viscosity, and specific heat in the initial state are input to the control device 20 in advance, and the pressure loss ΔP is calculated by the following equations (1) and (2).
ΔPc = (aWc ² + bWc + c) ρi ^ (3/4) μi ^ (1/4)… (1)
Wc = GrΔH / (ρiCpiΔTb)… (2)
Here, each symbol indicates the following contents. Wc: Brine flow rate calculation value, ρi: Brine density initial value, μi: Brine viscosity initial value, Cpi: Brine specific heat initial value, Gr: Refrigerant flow rate, ΔH: Heat exchanger inlet / outlet enthalpy difference, ΔTb: Brine inlet / outlet temperature difference, a , B, c: Value specific to the heat exchanger.

The control device 20 compares the calculated pressure loss ΔPc with the actually measured pressure loss ΔP measurement value. When the brine concentration increases, the density and viscosity of the brine generally increase and the specific heat decreases, so that the pressure loss ΔPc calculated from the initial physical property values becomes smaller than the actually measured pressure loss ΔP. Further, when the flow path of the second heat exchanger 7 is blocked, the calculated pressure loss ΔPc becomes smaller than the actually measured pressure loss ΔP. The control device 20 determines that the condition F is satisfied when ΔP> ΔPc is satisfied.

(5) Brine pipe blockage When the above-mentioned condition D and the following conditions H and J are satisfied, the control device 20 issues a notification of the brine pipe blockage in a portion other than the second heat exchanger 7.

[D: Decreased cooling capacity]
When the brine pipe is closed in a portion other than the second heat exchanger 7, the brine flow rate decreases, so that the heat exchange efficiency of the second heat exchanger 7 decreases. In a chiller or a heat pump that constantly controls SH when the heat exchange efficiency decreases, it is necessary to reduce the opening degree of the expansion valve 8 to reduce the evaporation temperature. In this case, the cooling capacity is reduced.

[H: Pressure loss reduction]
When the brine pipes other than the second heat exchanger 7 are blocked, the brine flow rate decreases, so that the pressure loss ΔP in the second heat exchanger 7 decreases. The control device 20 determines that the condition (H: decrease in pressure loss) is satisfied when the pressure loss ΔP obtained from the current measured value is lower than the pressure loss ΔPrem in the steady state.

[I: Pump current value increase]
When the brine pipes other than the second heat exchanger 7 are blocked, the current value Ip of the pump 2 increases. The control device 20 determines that the condition (I: pump current value increase) is satisfied when the current value Ip detected by the current sensor 11 is larger than the current value Iprem stored in advance.

(6) Brine flow rate reduction When the above-mentioned conditions D and H and the following condition K are satisfied, the control device 20 issues a notification of the brine flow rate reduction.

[D: Decreased cooling capacity]
When the brine flow rate decreases, the heat exchange efficiency in the second heat exchanger 7 decreases. In a chiller or a heat pump that constantly controls SH when the heat exchange efficiency decreases, it is necessary to reduce the opening degree of the expansion valve 8 to reduce the evaporation temperature. In this case, the cooling capacity is reduced.

[H: Pressure loss reduction]
When the brine flow rate decreases, the pressure loss ΔP in the second heat exchanger 7 decreases. The control device 20 determines that the condition (H: decrease in pressure loss) is satisfied when the pressure loss ΔP obtained from the current measured value is lower than the pressure loss ΔPrem in the steady state.

[K: Pump current value decrease]
When air enters the pump 2 and the pump 2 spins, the brine flow rate decreases. In this case, the current value of the pump 2 decreases. The decrease in the current value is detected by the current sensor 11. The control device 20 determines that the condition of [K: decrease in pump current value] is satisfied when the current value of the current sensor 11 falls below the determination value.

FIG. 4 is a flowchart for explaining a procedure for determining the determination content notified by the control device 20. With reference to FIGS. 3 and 4, the control device 20 first determines in step S1 about the change in the cooling capacity Qc using the determination formula 1 of FIG.

If it is determined in step S1 that the cooling capacity Qc has increased, the process proceeds to step S2. On the other hand, if it is determined in step S1 that the cooling capacity Qc has decreased, the process proceeds to step S5.

In step S2, the control device 20 determines the change in the pressure loss ΔP using the determination formula 2 of FIG. If it is determined in step S2 that the pressure loss ΔP has increased, the process proceeds to step S3. In step S3, the control device 20 displays on the display unit 23 that the abnormality determination content is “(1) Increase in brine flow rate”. On the other hand, if it is determined in step S2 that the pressure loss ΔP has decreased, the process proceeds to step S4. In step S4, the control device 20 displays on the display unit 23 that the abnormality determination content is "(2) Brine concentration decrease".

On the other hand, in step S5, the control device 20 determines the change in the pressure loss ΔP using the determination formula 2 of FIG.

If it is determined in step S5 that the pressure loss ΔP has increased, the process proceeds to step S6. On the other hand, if it is determined in step S5 that the pressure loss ΔP has decreased, the process proceeds to step S9.

In step S6, the control device 20 compares the magnitude of the pressure loss ΔP and the calculated value ΔPc as shown in the column of the determination formula 3 in FIG.

If ΔP> ΔPc in step S6, the process proceeds to step S7. In step S7, the control device 20 displays on the display unit 23 that the abnormality determination content is “(3) Increase in brine concentration”.

On the other hand, if ΔP <ΔPc in step S6, the process proceeds to step S8. In step S8, the control device 20 displays on the display unit 23 that the abnormality determination content is “(4) blockage of the flow path of the heat exchanger”.

In step S9, the control device 20 compares the magnitude of the current value Ip flowing through the pump 2 with the normal current value Iprem as shown in the column of the determination formula 3 in FIG.

If Ip> Iprem in step S9, the process proceeds to step S10. In step S10, the control device 20 displays on the display unit 23 that the abnormality determination content is “(5) Brine pipe blockage”.

On the other hand, if Ip <Iprem in step S9, the process proceeds to step S11. In step S11, the control device 20 displays on the display unit 23 that the abnormality determination content is “(6) Brine flow rate reduction”.

If the abnormality determination content is displayed in any of steps S3, S4, S7, S8, S10, and S11, the control device 20 stops the operation of the refrigeration cycle device 100 after a certain period of time has elapsed.

On the other hand, in the determination of steps S1, S2, S5, S6, and S9, if the parameters to be determined are as usual, the control is once returned to the main routine, and after a certain period of time has elapsed or when it becomes necessary to determine an abnormality. , The abnormality determination process of FIG. 4 is executed again.

Since the refrigeration cycle device according to the present embodiment can detect an abnormality in the load side circuit even when the physical properties of the heat medium change, it is possible to appropriately protect the refrigeration cycle device.

[Modification example]
FIG. 5 is a diagram showing the configuration of the refrigeration cycle device 100A of the first modification. In the refrigeration cycle device 100A shown in FIG. 5, the pump 2, the

pressure sensors

3 and 4, the

temperature sensors

9 and 10, and the control device 20 are housed in the heat source machine 1A together with the refrigerant circuit 40.

FIG. 6 is a diagram showing the configuration of the refrigeration cycle device 100B of the second modification. The refrigeration cycle apparatus 100B shown in FIG. 6 includes a plurality of refrigeration cycle units 1-1 to 1-N. The plurality of refrigeration cycle units 1-1 to 1-N each include a plurality of circuits in which the refrigerant circulates independently of each other. Each of the plurality of refrigeration cycle units 1-1 to 1-N includes a refrigerant circuit having a configuration similar to that of the refrigerant circuit 40 shown in FIG. A plurality of heat exchangers 7-1 to 7-N included in each of the plurality of refrigeration cycle units 1-1 to 1-N are arranged in series in the flow path of the heat medium of the load circuit 50. The first pressure sensor 3 is arranged in the inlet side flow path of the heat exchanger 7-1 arranged at the uppermost stream of the flow path among the plurality of heat exchangers 7-1 to 7-N, and the second pressure sensor 4 Is arranged in the outlet side flow path of the heat exchanger 7-N arranged at the most downstream of the flow path among the plurality of heat exchangers 7-1 to 7-N.

The same abnormality determination processing can be applied to the above modified examples. Therefore, it is possible to provide appropriate protection for the refrigeration cycle device.

(summary)
The refrigeration cycle apparatus 100 according to the present embodiment will be summarized again with reference to FIG.

This disclosure relates to the refrigeration cycle device 100. The refrigeration cycle device 100 includes a refrigerant circuit 40 that circulates the refrigerant. The refrigerant circuit 40 is configured to circulate the refrigerant so as to repeat a compression process, a condensation process, an expansion process, and an evaporation process. The refrigerant circuit 40 is configured by connecting the compressor 5, the first heat exchanger 6, the expansion valve 8 which is a decompression device, and the second heat exchanger 7 in an annular shape. The second heat exchanger 7 is configured to exchange heat between the refrigerant and the heat medium. The refrigeration cycle device 100 has a first pressure sensor 3 for detecting the pressure of the heat medium in the inlet side flow path of the heat medium of the second heat exchanger 7 and an outlet side flow path of the heat medium of the second heat exchanger 7. A second pressure sensor 4 for detecting the pressure of the heat medium is further provided.

A load device 30 that uses a heat medium is connected to the second heat exchanger 7. The refrigeration cycle device 100 further includes a control device 20 that receives the output of the first pressure sensor 3 and the output of the second pressure sensor 4. Based on the output of the first pressure sensor 3 and the output of the second pressure sensor 4, the control device 20 determines whether or not there is an abnormality in the load circuit 50 that circulates the heat medium in the load device 30, and the load circuit 50 has an abnormality. If it is recognized, an alarm is output.

The heat medium is water or brine. The load circuit 50 includes a pump 2 that circulates a heat medium between the second heat exchanger 7 and the load device 30. The control device 20 classifies and notifies the abnormality of the load circuit 50 based on the current value of the pump 2 in addition to the output of the first pressure sensor 3 and the output of the second pressure sensor 4.

Preferably, the refrigerant circuit 40 is housed in the heat source machine 1. The heat source machine 1 has a built-in pump 2 that circulates a heat medium.

Preferably, the refrigeration cycle apparatus includes a plurality of refrigeration cycle units 1-1 to 1-N. The plurality of refrigeration cycle units 1-1 to 1-N each include a plurality of circuits in which the refrigerant circulates independently of each other. Each of the plurality of refrigeration cycle units 1-1 to 1-N includes a refrigerant circuit having a configuration similar to that of the refrigerant circuit 40. A plurality of heat exchangers 7-1 to 7-N included in each of the plurality of refrigeration cycle units 1-1 to 1-N are arranged in series in the flow path of the heat medium. The first pressure sensor 3 is arranged in the inlet side flow path of the heat exchanger 7-1 arranged at the uppermost stream of the flow path among the plurality of heat exchangers 7-1 to 7-N, and the second pressure sensor 4 Is arranged in the outlet side flow path of the heat exchanger 7-N arranged at the most downstream of the flow path among the plurality of heat exchangers 7-1 to 7-N.

In the present embodiment, the case where the capacity control method of the compressor 5 is the rotation speed control by the inverter has been described, but other methods may be used. For example, a capacity control method for mechanically changing the stroke volume of the compressor 5 may be used, or a plurality of compressors 5 may be provided and the capacity of the compressor 5 may be controlled by changing the number of operating units thereof. ..

Further, the configuration of the second heat exchanger 7 is illustrated by the plate heat exchanger, but the present invention is not limited to this, and other configurations such as a shell tube type and a double tube type may be used. good. The first heat exchanger 6 is not limited to the plate fin heat exchanger, and other types such as corrugated fins may be used. Further, as the first heat exchanger 6, not only the one using air as a medium but also the one using another medium such as water can be applied to realize the same effect.

The embodiments disclosed this time should be considered to be exemplary in all respects and not restrictive. The scope of the present invention is shown by the claims rather than the description of the embodiments described above, and is intended to include all modifications within the meaning and scope equivalent to the claims.

1,1A, 1B heat source machine, 1-1 to 1-N refrigeration cycle unit, 2 pump, 3,4 pressure sensor, 5 compressor, 6,7,7-1 to 7-N heat exchanger, 8 expansion valve , 11 current sensor, 12 fan, 20 control device, 21 CPU, 22 memory, 23 display unit, 30 load device, 40 refrigerant circuit, 50 load circuit, 100, 100A, 100B refrigeration cycle device.

Claims

A refrigerant circuit configured to circulate the refrigerant in a repeating compression, condensation, expansion, and evaporation process.
The refrigerant circuit includes a heat exchanger configured to exchange heat between the refrigerant and a heat medium.
A first pressure sensor that detects the pressure of the heat medium in the inlet side flow path of the heat medium of the heat exchanger, and
A refrigeration cycle apparatus further comprising a second pressure sensor for detecting the pressure of the heat medium in the outlet side flow path of the heat medium of the heat exchanger.
A load device using the heat medium is connected to the heat exchanger.
The load device further includes a control device that receives the output of the first pressure sensor and the output of the second pressure sensor, and the control device is based on the output of the first pressure sensor and the output of the second pressure sensor. The refrigeration cycle device according to claim 1, wherein the refrigerating cycle apparatus according to claim 1 determines whether or not there is an abnormality in the load circuit that circulates the heat medium, and outputs an alarm when the load circuit is found to be abnormal.
The heat medium is water or brine and
The load circuit comprises a pump that circulates the heat medium between the heat exchanger and the load device.
The control device classifies and notifies an abnormality of the load circuit based on the current value of the pump in addition to the output of the first pressure sensor and the output of the second pressure sensor, according to claim 2. The refrigeration cycle device described.
The heat medium is water or brine and
The refrigeration cycle device further comprises a pump that circulates the heat medium between the heat exchanger and the load device.
The refrigerant circuit is housed in a heat source machine.
The refrigeration cycle apparatus according to claim 1, wherein a pump for circulating the heat medium is built in the heat source machine.
A plurality of refrigeration cycle units including a plurality of circuits in which refrigerants circulate independently of each other are provided, and the refrigerant circuit is included in one of the plurality of refrigeration cycle units.
A plurality of heat exchangers included in each of the plurality of refrigeration cycle units are arranged in series in the flow path of the heat medium.
The first pressure sensor is arranged in the inlet side flow path of the heat exchanger arranged at the uppermost stream of the flow path among the plurality of heat exchangers.
The refrigeration cycle device according to claim 1, wherein the second pressure sensor is arranged in the outlet side flow path of the heat exchanger arranged at the most downstream side of the flow path among the plurality of heat exchangers.