JPH0849936A - Regenerative air-conditioner - Google Patents

Abstract

PURPOSE:To prevent an excessive rise of a suction pressure of a compressor and prevent an excessive rise of a discharge pressure of the compressor by opening or closing a first expansion valve as a bypass valve of a heat exchanger for heat storage in accordance with the discharge pressure of the compressor on the occasion of a defrosting operation of a reverse cycle system of a heat- source-side heat exchanger at the time of a night heat-storing operation. CONSTITUTION:A night heat-storing operation mode wherein hot water is stored in a heat storage tank STR by using a heat exchanger 8a for heat storage is detected by a heat-storing operation mode detecting means 18. When a request for defrosting of a heat-source-side heat exchanger 4 is detected by a defrosting detecting means 19 on the occasion, a reverse-cycle defrosting operation wherein a first four-way valve 3a is made to function so that the heat exchanger 8a for heat storage be made an evaporator and the heat-source-side heat exchanger 4 a condenser is executed by a reverse-cycle defrosting drive means 22. In the case when a discharge pressure of a compressor 2 is higher than a prescribed one, during the reverse-cycle defrosting operation, a first expansion valve 5a is opened to a specified opening by a first expansion valve driving means 21.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an air conditioner using air as a heat source, and a heat storage type air conditioner having a heat storage / radiation function for utilizing nighttime electric power and a control function thereof.

[0002]

2. Description of the Related Art Various developments have already been made for a heat storage type air conditioner, for example, JP-A-3-144.
There is a heat storage type air conditioner as shown in Japanese Patent No. 236.

The basic technique will be described with reference to FIG.
As shown in, the outdoor unit 1 includes a compressor 2, a four-way valve 3a, a heat source side heat exchanger 4, a first expansion valve 5a, a first switching valve KV1,
A refrigerant-to-refrigerant heat exchanger HEX including a first auxiliary heat exchanger 7a and a second auxiliary heat exchanger 7b, a heat storage tank STR including a heat storage heat exchanger 8a and a heat radiation heat exchanger 8b, and a heat storage material. It is composed of water 9, a second switching valve KV2 that switches the flow path of the refrigerant, a refrigerant amount adjustment tank 11, and a liquid refrigerant transfer pump PM that transfers the liquid refrigerant. In addition, a plurality of indoor units 13
a and 13b are composed of utilization side heat exchangers 14a and 14b.

The refrigeration cycle on the heat source side includes a compressor 2,
Four-way valve 3a, heat source side heat exchanger 4, first expansion valve 5a, first
It is composed of a switching valve KV1, a first auxiliary heat exchanger 7a of the refrigerant-to-refrigerant heat exchanger HEX, and a heat storage heat exchanger 8a of the heat storage tank STR.

The utilization side refrigeration cycle includes a second auxiliary heat exchanger 7b of the refrigerant-refrigerant heat exchanger HEX, a heat radiating heat exchanger 8b of the heat storage tank STR, and a second switching valve KV for switching the refrigerant flow path.
2, a refrigerant amount adjustment tank 11, a liquid refrigerant transfer pump PM that transfers a liquid refrigerant, and indoor units 13a and 13b.

Next, the refrigerating cycle will be described. This refrigeration cycle is a night heat storage operation that produces hot water at night during heating (night ice making operation during ice cooling)
And the daytime heating operation (cooling operation). A detailed description of the daytime operation mode will be omitted, and the nighttime heat storage operation will be described.

Regarding the mode of the four-way valve 3a, the compressor 2
The case where the discharge side and the heat storage tank STR and the suction side of the compressor 2 and the heat source side heat exchanger 4 communicate with each other are defined as a heating mode.

With respect to the first switching valve KV1, the setting for connecting the heat storage tank STR and the first expansion valve 5a in the heat source side refrigeration cycle is defined as a first STR circuit.

In the heat source side refrigeration cycle, the heat storage tank ST
The first switching valve KV1 is switched to the first STR circuit so that R acts and the refrigerant-to-refrigerant heat exchanger HEX does not act. At this time, the liquid refrigerant transfer pump PM is stopped, and the use side refrigeration cycle does not operate. The operation of the heat source side refrigeration cycle will be described below.

The four-way valve 3a is a heating mode, and the first expansion valve 5a.
Is a predetermined opening degree, and the first switching valve KV1 is a first STR circuit. At this time, the high-temperature and high-pressure refrigerant sent from the compressor 2 is
It condenses in the heat storage heat exchanger 8a of the heat storage tank STR and heats the water 9, which is a heat storage material. After that, the pressure is reduced by the first expansion valve 5a to become a liquid or two-phase state, and the heat source side heat exchanger 4
Then, it evaporates and returns to the compressor 2. By such an action, the water in the heat storage tank STR becomes hot water and heat is stored.

As described above, the surplus power energy at night is converted into heat and stored, and the heat energy
By using, the installed capacity of the heat source machine can be reduced,
In addition, power usage can be leveled.

[0012]

However, in the above-mentioned conventional example, the heat source side heat exchanger 4 in the night heat storage operation mode is used.
In the defrosting (defrosting), when the reverse cycle method of defrosting by using the heat storage heat exchanger 8a as an evaporator and the heat source side heat exchanger 4 as a condenser, the water temperature in the heat storage tank STR is When the value is high, the evaporating pressure rises excessively due to the water temperature in the heat storage tank STR, and the discharge pressure of the compressor 2 rises excessively. There is a problem of reduction. On the other hand, when the forward cycle method of defrosting by increasing the evaporation pressure is used, there is a problem that the defrost time becomes long and the operation efficiency decreases, and there are advantages and disadvantages as the defrost of the heat source side heat exchanger 4 It had the drawback of lacking proper control.

In view of the above drawbacks, the present invention has an object to provide a heat storage type air conditioner capable of performing normal control by defrosting the heat source side heat exchanger 4 in the night heat storage operation mode. It is a thing.

[0014]

The technical means of the present invention for solving the above-mentioned problems is to provide a compressor, a first four-way valve, a heat source side heat exchanger, a first auxiliary heat exchanger and a second auxiliary heat. A first auxiliary heat exchange of the refrigerant-to-refrigerant heat exchanger, which comprises an exchanger, and a first expansion valve, a second expansion valve, a heat storage heat exchanger, a heat radiating heat exchanger, and a heat storage tank. A heat source side refrigeration cycle in which a heat storage heat exchanger is connected in parallel with the first auxiliary heat exchanger of the refrigerant-refrigerant heat exchanger and the first expansion valve, a liquid refrigerant transfer pump, and a second four-way valve. A pump unit including a refrigerant tank, a plurality of indoor units including a use-side heat exchanger, an indoor flow valve, and an indoor fan are connected to each other, and a first flow valve, a second auxiliary heat exchanger, and a second flow valve. And a heat-sink for heat dissipation and a user-side refrigeration cycle in which a two-way valve is connected in parallel, A heat storage operation mode detecting means for detecting that it is a nighttime heat storage operation mode for storing hot water in the heat storage tank by using a heat storage heat exchanger, and a defrosting request for the heat source side heat exchanger is detected. Defrost detecting means, compressor discharge pressure detecting means for detecting discharge pressure of the compressor, and first expansion valve for driving the first expansion valve based on information obtained by the compressor discharge pressure detecting means. When the defrosting request is detected by the driving means and the defrosting detecting means, the first four-way valve acts so that the heat storage heat exchanger serves as an evaporator and the heat source side heat exchanger serves as a condenser. And a first control device composed of a reverse cycle defrost driving means.

Further, a heat storage operation mode detecting means for detecting the night heat storage operation mode for storing hot water in the heat storage tank by using the heat storage heat exchanger, and the heat source side heat exchanger. Defrost detection means for detecting a defrost request, heat storage tank water temperature detection means for detecting the water temperature in the heat storage tank, and defrost mode determination for judging whether the cycle is a forward cycle defrost method or a reverse cycle defrost method based on the water temperature. Means, and a reverse cycle defrost driving means for causing the heat storage heat exchanger to act on an evaporator and the heat source side heat exchanger to act on a condenser,
A second control device comprising a forward cycle defrost driving means for causing the heat storage heat exchanger to act as a condenser and the heat source side heat exchanger to act as an evaporator.

[0016]

The heat storage type air conditioner of the present invention detects the nighttime heat storage operation mode in which hot water is stored in the heat storage tank by using the heat storage heat exchanger by the heat storage operation mode detection means, And, when the defrosting request of the heat source side heat exchanger is detected by the defrosting detecting means, the heat storage side heat exchanger is condensed by the reverse cycle defrost driving means, and the heat source side heat exchanger is condensed. Reverse cycle defrost operation is performed in which the first four-way valve is actuated so as to function as a container and defrosting is performed.

When the discharge pressure of the compressor detected by the compressor discharge pressure detecting means is higher than a predetermined pressure, until the defrosting request of the heat source side heat exchanger is canceled by the first expansion valve driving means. The first expansion valve is opened to a predetermined opening.

According to the above operation, during the reverse cycle defrost operation of the heat source side heat exchanger during night heat storage operation, the first expansion valve is used as a bypass valve of the heat storage heat exchanger according to the compressor discharge pressure. Since it is opened and closed, it is possible to prevent an excessive rise in the compressor suction pressure and prevent an excessive rise in the compressor discharge pressure.

Therefore, normal defrosting operation is performed to prevent high pressure cut of the compressor, and there is an effect that system reliability can be secured.

Further, the heat storage operation mode detection means detects the nighttime heat storage operation mode, and the defrost detection means detects the defrosting request of the heat source side heat exchanger.

When the defrost mode determination means detects the defrosting request and the water temperature is lower than the predetermined temperature, the reverse cycle defrosting driving means eliminates the defrosting request for the reverse cycle defrosting operation. When the water temperature is higher than the predetermined temperature, the forward cycle defrost driving means carries out the forward cycle defrost operation until the defrosting request disappears.

Therefore, when the water temperature is high, the forward cycle defrost system is used, so that the problem of high pressure cut of the compressor is eliminated and the reliability of the system is improved, and when the water temperature is low, the reverse cycle defrost system is used. Therefore, the defrost time is short and the heating operation efficiency is improved.

[0023]

Embodiments of the present invention will be described below with reference to the accompanying drawings. The same components as those in the prior art will be designated by the same reference numerals and detailed description thereof will be omitted.

FIG. 1 is a refrigeration cycle diagram of the first embodiment of the present invention. The heat storage type air conditioner of the present embodiment includes an outdoor unit 1 ', a heat storage tank STR, a pump unit PU, and indoor units 13a and 13b.

The outdoor unit 1'includes a compressor 2, a first four-way valve 3a, a heat source side heat exchanger 4, a first expansion valve 5a, a second expansion valve 5b, an outdoor fan 6, and a first auxiliary heat exchanger 7a. A refrigerant-to-refrigerant heat exchanger HEX including a second auxiliary heat exchanger 7b,
First flow valve RV1 for second auxiliary heat exchanger 7b, heat storage tank S
It is composed of a second flow valve RV2 for the heat radiating heat exchanger 8b of TR.

The heat storage tank STR comprises water 9 as a heat storage material, a heat storage heat exchanger 8a, and a heat radiation heat exchanger 8b. The pump unit PU is a refrigerant tank 11 and a liquid refrigerant transfer pump P.
The indoor unit 13 including the M and the second four-way valve 3b.
a and 13b are composed of utilization side exchangers 14a and 14b and indoor flow valves 15a and 15b.

In the above structure, the heat source side refrigeration cycle includes the compressor 2, the first four-way valve 3a, and the heat source side heat exchanger 4.
And the first auxiliary heat exchanger 7 of the refrigerant-to-refrigerant heat exchanger HEX, which includes the first auxiliary heat exchanger 7a and the second auxiliary heat exchanger 7b.
a, the first expansion valve 5a, the second expansion valve 5b, the heat storage heat exchanger 8a, the heat radiation heat exchanger 8b, and the heat storage material 9, and the heat storage heat exchanger 8a is used as a refrigerant-to-refrigerant. The first auxiliary heat exchanger 7a of the heat exchanger HEX and the first expansion valve 5a are connected in parallel.

The use side refrigeration cycle connects the liquid refrigerant transfer pump PM, the second four-way valve 3b, the refrigerant tank 11, the use side heat exchangers 14a and 14b and the indoor flow valves 15a and 15b, and the first flow rate. The valve RV1 and the second auxiliary heat exchanger 7b,
And the second flow valve RV2, the heat radiation heat exchanger 8b, and the two-way valve N.
V (preferably solenoid valves) are connected in parallel.

A heat storage operation mode detecting means 18 for detecting the night heat storage operation mode in which hot water is stored in the heat storage tank STR using the heat storage heat exchanger 8a, and the heat source side heat exchanger 4 Based on the information obtained by the defrosting detection means 19 for detecting the defrosting request of the compressor, the compressor discharge pressure detection means 20 for detecting the discharge pressure Pd (MPa) of the compressor 2, and the compressor discharge pressure detection means 20. Drive the first expansion valve 5a
When the expansion valve drive means 21 and the defrosting detection means 19 detect a defrosting request, the heat storage heat exchanger 8a serves as an evaporator, and the heat source side heat exchanger 4 serves as a condenser. The first control device CN1 is composed of a reverse cycle defrost drive means 22 for actuating 3a.

Here, the discharge portion pressure sensor 17 of the compressor 2
Is shown as a specific example of the compressor discharge pressure detection means 20.

Next, the operation of the structure of the first embodiment will be described. Here, the first switching valve K described in the conventional example
A first expansion valve 5a and a second expansion valve 5b instead of V1;
The first flow valve RV1 and the second flow valve RV2 are used instead of the second switching valve KV2. The first STR circuit is set to communicate the heat storage tank STR and the first expansion valve 5a in the heat source side refrigeration cycle, and the first HEX circuit is set to communicate the refrigerant-refrigerant heat exchanger HEX and the second expansion valve 5b. By definition, the operation is the same as that of the conventional example except the operation of the first control device CN1, and therefore the description of the operation of each operation pattern is omitted. The operation of the first control device CN1 different from the conventional example will be described with reference to the flowchart of FIG.

In STEP 1, the heat storage operation mode detection means 18 detects whether or not it is the night heat storage operation mode. If it is the night heat storage operation mode, the process proceeds to STEP 2, otherwise the routine is executed. Get out of the chin.

In STEP 2, the defrosting detection means 19 detects whether or not there is a defrosting request for the heat source side heat exchanger 4, and if there is a request, the process proceeds to STEP 3;
Get out of the chin.

STEP 3 is compressor discharge pressure detection means 2
0 to detect the discharge pressure Pd (MPa) of the compressor 2,
Pd is a predetermined value P1 or more (for example, Pd ≧
(1.8 MPa), there is a risk that the compressor discharge pressure will be cut off during defrosting, so the heat storage heat exchanger 8a
If it is determined that the bypass is necessary, the process shifts to STEP 4, and otherwise it is determined that the bypass is not necessary, and the process proceeds to ST.
Move to EP5.

In STEP 4, the first expansion valve drive means 21
To fully open the first expansion valve 5a as a bypass of the heat storage heat exchanger 8a (for example, 2000 pulses in the case of an electronic expansion valve)
Then, the process proceeds to STEP5.

By the operations of STEP3 to STEP4, the existing first expansion valve 5 is operated during the reverse cycle defrost operation.
Since a is used as a bypass valve of the heat storage heat exchanger 4 to open and close according to the compressor discharge pressure Pd, it is possible to prevent the compressor suction pressure Ps from rising excessively and prevent the compressor discharge pressure Pd from rising excessively.

STEP 5 to STEP 6 are operations of the reverse cycle defrost operation. At STEP 5, the first four-way valve 3a is turned off by the reverse cycle defrost drive means 22.
As F (cooling mode), the process proceeds to STEP6.

In STEP 6, the outdoor fan 6 is stopped by the reverse cycle defrost driving means 22 and the process proceeds to STEP 7.

In STEP 7, the defrosting detection means 19 detects whether or not there is a defrosting request for the heat source side heat exchanger 4, and if there is a request, the process proceeds to STEP 3, otherwise it is determined that defrosting has ended. Move to STEP8.

At STEP 8, the outdoor fan 6 is turned on to return to the original night heat storage operation mode, and the process proceeds to STEP 9.

Similarly to STEP8, STEP9 also turns ON the first four-way valve 3a (heating mode) and shifts to STEP10.

In STEP 10, the first expansion valve 5a previously operated in STEP 4 is fully closed (for example, in the case of an electronic expansion valve, 0).
Pulse) and then exit the routine.

In this way, from STEP1 to STEP1
The routine of 0 is repeated during the heating operation.

As described above, in the heat storage type air conditioner of the above embodiment, the heat storage operation mode detecting means 18 uses the heat storage heat exchanger 8a to store hot water in the heat storage tank STR at night. Defrosting and defrost detection means 19
When the defrosting request for the heat source side heat exchanger 4 is detected by the reverse cycle defrost driving means 22, the heat storage side heat exchanger 8a is used as an evaporator and the heat source side heat exchanger 4 is used as a condenser. Reverse cycle defrost operation for defrosting by operating the four-way valve 3a is performed.

During the reverse cycle defrost operation, when the discharge pressure Pd of the compressor 2 detected by the compressor discharge pressure detection means 20 is higher than the predetermined pressure P1, the first expansion valve drive means 21 performs heat exchange on the heat source side. The first expansion valve 5a is opened to a predetermined opening until the defrosting request for the container 4 is exhausted.

By the above operation, during the reverse cycle defrosting operation of the heat source side heat exchanger 4 during the nighttime heat storage operation, the existing first expansion valve 5a is used as a bypass valve of the heat storage heat exchanger 4 to discharge the compressor. Since it opens and closes according to the pressure Pd,
Compressor suction pressure Ps can be prevented from rising excessively, and compressor discharge pressure P
It is possible to prevent excessive rise of d.

Therefore, normal defrosting operation is performed to prevent high pressure cut of the compressor, and there is an effect that the reliability of the system can be secured.

The second embodiment will be described with reference to the accompanying drawings. The same components as those in the first embodiment will be designated by the same reference numerals and detailed description thereof will be omitted.

FIG. 4 is a refrigeration cycle diagram in the second embodiment of the present invention. The configuration of the second embodiment is the first
In place of the first controller CN1 and the discharge part pressure sensor 17 in the above embodiment, the second controller CN2 and the server CN2.
Since the configuration is the same as that of the first embodiment except that the mister 23 is used, a different second control device CN2 and server are used.
Only the mister 23 will be described.

The second control device CN2 includes a heat storage heat exchanger 8
Heat storage operation mode detection means 1 for detecting that it is a nighttime heat storage operation mode in which hot water is stored in the heat storage tank STR using a.
8, defrost detection means 19 for detecting a defrost request of the heat source side heat exchanger 4, heat storage tank water temperature detection means 24 for detecting the water temperature Tw in the heat storage tank STR, and a forward cycle defrost method based on the water temperature Tw. Defrost mode determining means 25 for determining whether it is a reverse cycle defrost system or a heat storage heat exchanger 8
Reverse cycle defrost drive means 22 for acting a on the evaporator and heat source side heat exchanger 4 on the condenser, heat storage heat exchanger 8a on the condenser, and heat source side heat exchanger 4 on the evaporator. And a forward cycle defrost driving means 26.

Here, the thermistor 23 is shown as a specific example of the heat storage tank water temperature detecting means 24.

Next, the operation of the configuration of the second embodiment will be described. Here, except for the operation of the second control device CN2, the operation is the same as that of the first embodiment, so the description of the operation of each operation pattern is omitted. The operation of the second control device CN2 different from that of the first embodiment will be described with reference to the flow chart of FIG.

In STEP 1, the heat storage operation mode detection means 18 detects whether or not the mode is the night heat storage operation mode. If it is the night heat storage operation mode, the process proceeds to STEP 2, otherwise the routine is executed. Get out of the chin.

In STEP 2, the defrosting detection means 19 detects whether or not there is a defrosting request for the heat source side heat exchanger 4, and if there is a request, the process proceeds to STEP 3;
Get out of the chin.

In STEP 3, the heat storage tank water temperature detection means 24 detects the water temperature Tw in the heat storage tank STR, and the defrost mode determination means 25 detects the water temperature Tw below a predetermined value T1 (for example, Tw≤45 ° C.). If so, it is determined that the reverse cycle defrost method is used, and the process proceeds to STEP4. Otherwise, it is determined that the forward cycle defrost system is used and the process proceeds to STEP5.

In STEP 4, the first expansion valve 5a is fully opened (for example, 2000 pulses in the case of an electronic expansion valve) as a bypass of the heat storage heat exchanger 8a, and the process proceeds to STEP 6.

At STEP 6, the reverse cycle defrost drive means 22 turns off the first four-way valve 3a (cooling mode).
Then, the process proceeds to STEP7.

In STEP 7, the outdoor fan 6 is stopped by the reverse cycle defrost driving means 22 and the process proceeds to STEP 8.

Here, in the operation of STEP 4, since the first expansion valve 5a is previously opened as a bypass valve of the heat storage heat exchanger 4 during the reverse cycle defrost operation, it is necessary to excessively raise the compressor suction pressure Ps. The purpose is to minimize and prevent the compressor discharge pressure Pd from rising excessively.

STEP 6 to STEP 7 are operations of the reverse cycle defrost operation. In STEP8, the defrosting detection means 19 detects whether or not there is a defrosting request for the heat source side heat exchanger 4, and until the defrosting request is exhausted, STEP8
If the defrosting request is not made, it is determined that the defrosting is completed and the process proceeds to STEP 9.

At STEP 9, the outdoor fan 6 is turned on to return to the original night heat storage operation mode, and the process proceeds to STEP 9.

STEP10 is the same as STEP9 in the first step.
The four-way valve 3a is turned on (heating mode), and the process proceeds to STEP11.

In STEP 11, the first expansion valve 5a previously operated in STEP 4 is fully closed (for example, 0 in the case of an electronic expansion valve).
Pulse) and then exit the routine.

On the other hand, in STEP 5, the second cycle expansion valve 5b is fully opened (for example, 2000 pulses in the case of an electronic expansion valve) by the forward cycle defrost drive means 27, and STEP 1
Move to 2.

In STEP 12, the outdoor fan 6 is stopped by the forward cycle defrost driving means 27 and STEP is started.
Move to 13.

In STEP 13, the defrost detecting means 19 detects whether or not there is a defrost request for the heat source side heat exchanger 4, and the continuous operation is performed in STEP 13 until the defrost request is exhausted. If it is judged that defrosting has ended, ST
Move to EP14.

In STEP 14, the outdoor fan 6 is turned on to return to the normal night heat storage operation mode, and STEP 15
Move to

Similarly to STEP 14, STEP 15 also completely closes the second expansion valve 5b (for example, 0 pulse in the case of an electronic expansion valve), and then exits the routine.

In this way, from STEP 1 to STEP 1
The routine of 5 is repeated during the heating operation.

As described above, in the above embodiment, in the heat storage type air conditioner, the heat storage operation mode detection means 18 detects the nighttime heat storage operation mode, and the defrost detection means 19 causes the heat source side heat exchanger. If the defrost mode determination means 25 detects the defrosting request of No. 4 and the water temperature Tw in the heat storage tank STR is lower than the predetermined temperature T1, the reverse cycle defrost drive means 22 performs the reverse cycle defrost operation. When the water temperature Tw is higher than the predetermined temperature, the forward cycle defrost driving means 26 performs the forward cycle defrost operation until the defrost request is eliminated.

Therefore, when the water temperature Tw is high, the forward cycle defrost system is used, so that the problem of high pressure cut of the compressor is eliminated and the system reliability is improved, and when the water temperature Tw is low, the reverse cycle defrost system is used. Therefore, the defrost time is short and the heating operation efficiency is improved.

[0072]

As described above, the present invention is a heat storage type air conditioner comprising a heat source side refrigeration cycle and a utilization side refrigeration cycle through a heat storage tank, and heat storage heat exchange by heat storage operation mode detection means. When the night heat storage operation mode for storing hot water in the heat storage tank is detected using the heat exchanger, and the defrosting request of the heat source side heat exchanger is detected by the defrosting detecting means, the heat storage by the reverse cycle defrost driving means is performed. Reverse cycle defrost operation is performed in which the first four-way valve is operated so that the heat exchanger for use as an evaporator and the heat exchanger on the heat source side as a condenser act to defrost.

When the discharge pressure of the compressor detected by the compressor discharge pressure detecting means is higher than the predetermined pressure during the reverse cycle defrost operation, the first expansion valve driving means defrosts the heat source side heat exchanger. First until demand is exhausted
Open the expansion valve to the specified opening.

By the above operation, during the reverse cycle defrost operation of the heat source side heat exchanger during night heat storage operation, the first expansion valve serves as a bypass valve of the heat storage heat exchanger and the discharge pressure of the compressor. Therefore, the compressor suction pressure can be prevented from rising excessively, and the compressor discharge pressure can be prevented from rising excessively.

Therefore, since the compressor high pressure cut is prevented, the normal defrost operation is performed, and the system reliability can be secured.

When the heat storage operation mode detection means detects the night heat storage operation mode and the defrost detection means detects the defrosting request of the heat source side heat exchanger, By the defrost mode discrimination means,
When the water temperature is lower than the predetermined temperature, the reverse cycle defrost driving means carries out the reverse cycle defrost operation until the defrosting request disappears, and when the water temperature is higher than the predetermined temperature, the forward cycle defrost driving means. Thus, the forward cycle defrost operation is performed until the defrosting request disappears.

Therefore, when the water temperature is high, the forward cycle defrost method is used, so that the problem of high pressure cut of the compressor is eliminated and the reliability of the system is improved, and when the water temperature is low, the reverse cycle defrost method is used. Therefore, the defrost time is short and the heating operation efficiency is improved.

[Brief description of drawings]

FIG. 1 is a refrigeration system diagram of a heat storage type air conditioner according to a first embodiment of the present invention.

FIG. 2 is a block diagram of a control device in the embodiment.

FIG. 3 is an operation flowchart of the cooling and heating device of the same embodiment.

FIG. 4 is a refrigeration system diagram of a heat storage type air conditioner in a second embodiment of the present invention.

FIG. 5 is a block diagram of a control device in the embodiment.

FIG. 6 is an operation flowchart of the cooling and heating apparatus of the embodiment.

FIG. 7 is a refrigeration system diagram of a heat storage type air conditioner showing a conventional example.

[Explanation of symbols]

 2 Compressor 3a First four-way valve 3b Second four-way valve 4 Heat source side heat exchanger 5a First expansion valve 5b Second expansion valve 7a Refrigerant-refrigerant heat exchanger first auxiliary heat exchanger 7b Refrigerant-refrigerant heat exchanger Second auxiliary heat exchanger 8a Heat storage heat exchanger for heat storage tank 8b Heat dissipation heat exchanger for heat storage tank 13a, 13b Indoor unit STR Heat storage tank HEX Refrigerant-refrigerant heat exchanger PM Liquid refrigerant transfer pump RV1 First flow valve RV2 2nd flow valve NV 2 way valve CN1 1st control device

Claims (2)

[Claims] 1. A first auxiliary heat exchange of a refrigerant-refrigerant heat exchanger comprising a compressor, a first four-way valve, a heat source side heat exchanger, a first auxiliary heat exchanger and a second auxiliary heat exchanger. A first expansion valve, a second expansion valve, a second expansion valve, a heat storage heat exchanger, a heat radiation heat exchanger, and a heat storage heat exchanger of a heat storage tank comprising a heat storage material. 1 A heat source side refrigeration cycle connected in parallel with the auxiliary heat exchanger and the first expansion valve, a pump unit including a refrigerant transfer pump, a second four-way valve and a refrigerant tank, a heat exchanger on the use side and an indoor flow valve And a plurality of indoor units consisting of
It consists of an auxiliary heat exchanger and a utilization-side refrigeration cycle in which a second flow valve and the heat radiation heat exchanger are connected in parallel, and hot water is stored in the heat storage tank using the heat storage heat exchanger at night. Heat storage operation mode detection means for detecting heat storage operation mode, defrost detection means for detecting a defrost request of the heat source side heat exchanger, and compressor for detecting the discharge pressure of the compressor A defrost request is detected by the discharge pressure detection means, the first expansion valve drive means for driving the first expansion valve based on the information obtained by the compressor discharge pressure detection means, and the defrost detection means. And a first control device comprising reverse cycle defrost drive means for operating the first four-way valve so that the heat storage heat exchanger serves as an evaporator and the heat source side heat exchanger serves as a condenser. The first control device has the heat storage operation mode. The night heat storage operation mode in which hot water is stored in the heat storage tank by using the heat storage heat exchanger by the deodorization detection means, and the defrosting request of the heat source side heat exchanger by the defrosting detection means. When detected, reverse cycle defrost operation is performed in which the first four-way valve acts so that the heat storage heat exchanger serves as an evaporator and the heat source side heat exchanger serves as a condenser by the reverse cycle defrost driving means. When the discharge pressure of the compressor detected by the compressor discharge pressure detecting means is higher than a predetermined pressure, the first expansion valve driving means continues until the defrosting request of the heat source side heat exchanger is eliminated. A heat storage type air conditioner characterized by opening the first expansion valve to a predetermined opening. 2. A first auxiliary heat exchange of a refrigerant-refrigerant heat exchanger comprising a compressor, a first four-way valve, a heat source side heat exchanger, a first auxiliary heat exchanger and a second auxiliary heat exchanger. A first expansion valve, a second expansion valve, a second expansion valve, a heat storage heat exchanger, a heat radiation heat exchanger, and a heat storage heat exchanger of a heat storage tank comprising a heat storage material. 1 A heat source side refrigeration cycle connected in parallel with the auxiliary heat exchanger and the first expansion valve, a pump unit including a refrigerant transfer pump, a second four-way valve and a refrigerant tank, a heat exchanger on the use side and an indoor flow valve And a plurality of indoor units consisting of
It consists of an auxiliary heat exchanger and a utilization-side refrigeration cycle in which a second flow valve and the heat radiation heat exchanger are connected in parallel, and hot water is stored in the heat storage tank using the heat storage heat exchanger at night. Heat storage operation mode detection means for detecting that it is in heat storage operation mode, defrost detection means for detecting a defrost request of the heat source side heat exchanger, and heat storage tank for detecting the water temperature in the heat storage tank A water temperature detecting means, a defrost mode determining means for judging whether the system is a forward cycle defrost system or a reverse cycle defrost system based on the water temperature, a heat storage heat exchanger as an evaporator, and a heat source side heat exchanger as a condenser. Cycle defrost driving means for operating the heat storage side heat exchanger on the condenser and forward cycle defrost driving means for operating the heat source side heat exchanger on the evaporator. Have The second control device detects the nighttime heat storage operation mode in which hot water is stored in the heat storage tank using the heat storage heat exchanger by the heat storage operation mode detection means, and the defrosting detection is performed. When the defrosting request of the heat source side heat exchanger is detected by means, the defrost mode determination means, if the water temperature is lower than a predetermined temperature, reverse cycle defrost drive means to perform reverse cycle defrost operation. It is carried out until the defrosting request disappears, and when the water temperature is higher than a predetermined temperature, a forward cycle defrosting operation is carried out by the forward cycle defrosting driving means until the defrosting request disappears. Machine.