JP2008298335A - Refrigeration apparatus, additional refrigerant filling kit used for the refrigeration apparatus, and additional refrigerant charging method for refrigeration apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To automatically filling an additional refrigerant without badly affecting a compressor after a heat source-side unit and a use-side unit are connected through a refrigerant pipe. <P>SOLUTION: This refrigerating device where an outdoor unit 100 and an indoor unit 200 are connected through a liquid-side refrigerant pipe 161 and a gas-side refrigerant pipe 162, a receiver tank 140 having a liquid level detecting means 150 is disposed in the liquid-side refrigerant pipe 161 in the outdoor unit 100, and a three-way valve 163 is disposed in the gas-side refrigerant pipe 162, further the device comprises a solenoid valve 311 disposed between a refrigerant cylinder 300 and the three-way valve 163 in additionally filling the refrigerant, and an opening signal is output to the solenoid valve 311 to start the filling of the additional refrigerant when both of discharge-side overheat degree of compressor 110 SH1≥T1, and suction-side overheat degree SH2≥T2 are satisfied in a state of a cooling operation in additionally filling the refrigerant (T1, T2 are prescribed threshold values). <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a refrigeration apparatus applied to an air conditioner and the like, a refrigerant additional charging kit used in the refrigeration apparatus, and a refrigerant additional charging method for the refrigeration apparatus. It relates to filling technology.

  For example, there are multi air conditioners for buildings in the refrigeration system. In a building multi-air conditioner, a plurality of usage-side units (indoor units) are connected in parallel to one heat source side unit (outdoor unit) via a refrigerant pipe, but the scale of the building varies. For this reason, the pipe lengths differ accordingly.

  For this reason, in a building multi-air conditioner, after an outdoor unit and each indoor unit are connected to each other through a refrigerant pipe and evacuated, it may be necessary to additionally fill the refrigerant according to the length of the refrigerant pipe. . The additional charging of the refrigerant needs to be performed in an appropriate amount without excess or deficiency.

  Therefore, Patent Document 1 calculates and displays the amount of refrigerant to be additionally charged based on the piping length on the drawing in addition to the amount of refrigerant previously enclosed in the outdoor unit at the installation site of the air conditioner. A method has been proposed.

  However, the method described in Patent Document 1 is based on the premise that the actually installed pipe length and the pipe length on the drawing are substantially the same, and there is a difference between the actually installed pipe length and the pipe length on the drawing. If it exists, excess and deficiency will arise in a refrigerant | coolant amount, and will cause a malfunction.

  Patent Document 2 discloses a method of filling an additional refrigerant while monitoring the liquid level in the receiver tank (liquid receiver), and stopping charging of the refrigerant when the liquid level reaches a predetermined level. According to this, it is possible to automatically fill the refrigerant without using piping drawings or the like.

  By the way, when the refrigerant pipe is filled with the additional refrigerant, if the pressure in the pipe becomes equal to the pressure in the refrigerant cylinder, the refrigerant cannot be filled any more. Therefore, the air conditioner is in a cooling operation and is filled in the low-pressure side gas-side refrigerant pipe in the outdoor unit.

  This refrigerant filling point is a three-way valve provided in the gas side refrigerant pipe. However, since the liquid refrigerant filled from the three-way valve is directly sucked into the compressor, the liquid is charged if the refrigerant is filled too fast. There is a risk of damage to the compressor due to the back.

  In order to avoid this, conventionally, the refrigerant filling pace is adjusted by the valve opening of the refrigerant cylinder. However, not only the adjustment work is troublesome but also accurate adjustment is difficult. It is necessary to fill at a slower pace than necessary with an emphasis on this, which causes delays in construction work. Such a problem cannot be solved by the methods described in Patent Documents 1 and 2.

JP 11-63745 A JP 2006-38453 A

  Accordingly, an object of the present invention is to enable automatic charging of an additional refrigerant without adversely affecting the compressor after connecting the heat source side unit and the usage side unit via the refrigerant pipe. .

  In order to solve the above-described problems, the present invention provides a heat source side unit including a compressor, a heat source side heat exchanger, and an outdoor unit control unit, as described in claim 1, and a utilization side heat exchanger and A use side unit including a refrigerant expansion means is connected via a liquid side refrigerant pipe and a gas side refrigerant pipe, and a receiver tank having a liquid level detection means is provided in the liquid side refrigerant pipe in the heat source side unit. In the refrigeration apparatus provided with a flow path switching valve for connecting a refrigerant cylinder to the gas side refrigerant pipe in the heat source side unit, the refrigerant cylinder and the flow path switching valve are interposed between the refrigerant cylinder and the flow path switching valve. The flow control valve is controlled to be opened and closed by the outdoor unit control unit, the discharge side superheat degree of the compressor is SH1, its threshold is T1, the suction side superheat degree of the compressor is SH2, and its threshold is T2. In the additional refrigerant charging mode, the outdoor unit control unit has both the conditions of SH1 ≧ T1 (or SH1> T1) and SH2 ≧ T2 (or SH2> T2) with the refrigeration apparatus in the cooling operation. When satisfied, an open signal is output to the flow rate adjusting valve to fill the refrigerant.

  In this case, as described in claim 2, the outdoor unit controller closes the flow rate adjustment valve when SH1 <T1 (or SH1 ≦ T1) and / or SH2 <T2 (or SH2 ≦ T2). Outputs a signal to stop refrigerant filling.

  According to a third aspect of the present invention, the discharge side pressure of the compressor is HP, the lower and upper thresholds thereof are P1 and P2, the suction side pressure of the compressor is LP, and the lower and upper thresholds thereof. P3, P4, where the liquid level in the receiver tank detected by the liquid level detection means is RL, and the predetermined appropriate liquid level in the receiver tank is M, the outdoor unit control unit When P1 <HP <P2 (or P1 ≦ HP ≦ P2), P3 <LP <P4 (or P3 ≦ LP ≦ P4), and RL ≧ M (or RL> M) are all satisfied, A close signal is output to the flow rate adjusting valve to end the refrigerant charging.

  Further, as described in claim 4, the discharge-side superheat degree SH1 is obtained from the discharge refrigerant temperature and the high-pressure saturation temperature of the compressor, and the suction-side superheat degree SH2 is calculated from the intake refrigerant temperature of the compressor. It can be determined from the low pressure saturation temperature.

  In addition, as described in claim 5, in the use side unit, an inlet temperature sensor provided on the low pressure two-phase refrigerant inflow side of the use side heat exchanger and an outlet temperature sensor of the use side heat exchanger. The degree of superheat is controlled based on each temperature detected from the above.

  As described in claim 6, the present invention includes a flow rate adjusting valve that is controlled to be opened and closed by the outdoor unit control unit according to claim 1, and through a charging hose when the refrigerant is additionally charged. A refrigerant additional charging kit connected between the refrigerant cylinder and the flow path switching valve is also included.

  Further, in the present invention, as described in claim 7, a use side heat exchanger and a refrigerant expansion means are provided for a heat source side unit including a compressor, a heat source side heat exchanger, and an outdoor unit control unit. And a receiver tank having a liquid level detection means is provided in the liquid side refrigerant pipe in the heat source side unit, the use side unit including the receiver side unit being connected via the liquid side refrigerant pipe and the gas side refrigerant pipe. In the refrigerant additional charging method of the refrigeration apparatus in which the gas side refrigerant pipe in the side unit is provided with a flow path switching valve for connecting a refrigerant cylinder, the discharge-side superheat degree of the compressor is SH1, the threshold is T1, and the compression The suction side superheat degree of the compressor is SH2, its threshold is T2, the discharge side pressure of the compressor is HP, its lower and upper thresholds are P1 and P2, the suction side pressure of the compressor is LP, its lower threshold And the upper threshold value is P3, P4, the liquid level in the receiver tank detected by the liquid level detection means is RL, the predetermined appropriate liquid level in the receiver tank is M, and the refrigerant cylinder is the outdoor unit. After evacuating the refrigerant pipe on the indoor unit side in a state of being connected to the flow path switching valve via a flow rate control valve that is controlled to be opened and closed by the control unit, the flow path switching valve and the refrigerant cylinder valve are opened, With the flow rate regulating valve closed, the refrigeration system was cooled with only the initial charge of refrigerant, and both the conditions of SH1 ≧ T1 (or SH1> T1) and SH2 ≧ T2 (or SH2> T2) were satisfied. At this time, an open signal is output to the flow rate adjusting valve to fill the refrigerant in the refrigerant cylinder from the gas side refrigerant pipe side, and thereafter, P1 <HP <P2 (or P1 ≦ HP ≦ P ), P3 <LP <P4 (or P3 ≦ LP ≦ P4), and RL ≧ M (or RL> M) are satisfied, a close signal is output to the flow control valve to Also included is a refrigerant additional charging method for a refrigeration apparatus, characterized by terminating the refrigerant charging.

  According to the present invention, when the refrigerant is additionally charged, both of the conditions of SH1 ≧ T1 (or SH1> T1) and SH2 ≧ T2 (or SH2> T2) are satisfied while the refrigeration apparatus is in the cooling operation. Then, since it is safe even if the refrigerant is charged, an open signal is output to the flow rate adjustment valve, and charging of the additional refrigerant is started.

  On the other hand, when SH1 <T1 (or SH1 ≦ T1) and / or SH2 <T2 (or SH2 ≦ T2), the flow rate adjustment valve is closed because the liquid refrigerant has returned too much to the compressor. Stop filling the refrigerant.

  During the refrigerant charging, the following conditions are satisfied: P1 <HP <P2 (or P1 ≦ HP ≦ P2), P3 <LP <P4 (or P3 ≦ LP ≦ P4), and RL ≧ M (or RL> M). When this is done, a closing signal is output to the flow control valve to end the charging of the additional refrigerant, so that the additional refrigerant is not damaged by the liquid back to the compressor and at an appropriate charging pace. Can be filled automatically.

  Next, an embodiment of the present invention will be described with reference to FIGS. In this embodiment, the refrigeration apparatus of the present invention is applied to an air conditioner. FIG. 1 is a schematic diagram showing the overall configuration of the air conditioner. FIG. 2 is a flowchart for explaining operations during charging of additional refrigerant. 3 is a Mollier diagram for explaining the operation when the additional refrigerant is charged.

  As shown in FIG. 1, this air conditioner includes an outdoor unit 100 as a heat source side unit and an indoor unit 200 as a use side unit. In this example, the air conditioner is a multi-air conditioner with respect to one outdoor unit 100. Two indoor units 200 are connected in parallel.

  The outdoor unit 100 includes a compressor 110, a four-way valve 120, and an outdoor heat exchanger 130 connected to the compressor 110 via the four-way valve 120. The outdoor heat exchanger 130 is provided with an outdoor fan 131. In this example, a variable speed inverter fan 131 is used as the outdoor fan 131.

  The compressor 110 may be either a variable speed compressor controlled by an inverter or a constant speed compressor, but in this example, it is a variable speed compressor. A plurality of compressors 110 may be provided.

  The four-way valve 120 is a switching valve for switching between the cooling operation and the heating operation, and may be omitted in the case of cooling only or heating only. In the case of the cooling only machine, the outdoor heat exchanger 130 is connected to the high-pressure side (refrigerant discharge side) of the compressor 110.

  A liquid side refrigerant pipe 161 is drawn out from the outdoor heat exchanger 130, and a receiver tank (liquid receiver) 140 is provided in the middle of the liquid side refrigerant pipe 161.

  Further, in the outdoor unit 100, a gas side refrigerant pipe 162 is provided together with a liquid side refrigerant pipe 161. During the cooling operation, the gas side refrigerant pipe 162 is connected to the low pressure side (refrigerant suction side) of the compressor 110 via the four-way valve 120. ).

  The gas side refrigerant pipe 162 is provided with a flow path switching valve (in this example, a three-way valve) 163 for charging additional refrigerant. An accumulator 170 that separates and stores the liquid refrigerant is provided in the pipe from the four-way valve 120 to the low pressure side of the compressor 110.

  The receiver tank 140 is provided with a liquid level detecting means 150. In this example, the liquid level detection means 150 includes three liquid level detection pipes 151, 152, 153 including capillary tubes 151a, 152a, 153a as decompression means.

  The liquid level detection pipes 151, 152, and 153 are connected to different height positions of the receiver tank 140. In this example, the liquid level detection pipe 151 is used for high level detection, and the liquid level detection pipe 152 is used as a middle level. The level detection and liquid level detection pipe 153 is for low level detection.

  On the downstream side of the capillary tubes 151a, 152a, 153a, a heating means 154 for heating the refrigerant after decompression is provided. For the heating means 154, heat generated from the refrigerant discharge pipe of the compressor 110 is preferably used.

  The liquid level detection pipes 151, 152, and 153 are provided with temperature sensors 151b, 152b, and 153b for detecting the temperature of the refrigerant heated by the heating means 154, and the refrigerant temperature by each of these temperature sensors is the outdoor unit. Input to the control unit 180.

  The outdoor unit control unit 180 is arranged in the receiver tank 140 at a position where one end of the liquid level detection pipes 151, 152, 153 is connected based on the refrigerant temperature detected by the temperature sensors 151b, 152b, 153b. Detect the phase state of the refrigerant.

  The liquid level detection unit 150 is a liquid level detection unit disclosed in Japanese Patent Application Laid-Open No. 2006-250480 related to the applicant's application. In the present invention, another liquid level detection unit is used. Also good. The refrigerant passed through the liquid level detection pipes 151, 152, and 153 for liquid level detection is returned to the gas side refrigerant pipe 162.

  A temperature sensor 101 and a pressure sensor 103 are provided on the high pressure piping side of the compressor 110, and a temperature sensor 102 and a pressure sensor 104 are also provided on the low pressure piping side of the compressor 110. The detected value is given to the outdoor unit control unit 180.

  The indoor unit 200 includes an indoor heat exchanger (use side heat exchanger) 210. The indoor heat exchanger 210 is usually provided with an indoor fan composed of a cross flow fan, but the illustration thereof is omitted here. Also, the control unit on the indoor unit side is not shown.

  The indoor unit 200 also has a liquid side refrigerant pipe 201 and a gas side refrigerant pipe 202, and the liquid side refrigerant pipe 201 of the indoor unit 200 and the liquid side refrigerant pipe 161 of the outdoor unit 100 are connected via a connection valve 201a. The gas side refrigerant pipe 202 of the indoor unit 200 and the gas side refrigerant pipe 162 of the outdoor unit 100 are connected via a connection valve 202a.

  An electronic expansion valve 220 is provided on the liquid refrigerant pipe 201 side of the indoor heat exchanger 210, and an inlet temperature sensor 231 for detecting the refrigerant temperature on the electronic expansion valve 220 side of the indoor heat exchanger 210, and an indoor An intermediate temperature sensor 232 that detects the refrigerant temperature at an intermediate position of the heat exchanger 210 is provided.

  During the cooling operation, the high pressure side of the compressor 110 is connected to the outdoor heat exchanger 130 by the four-way valve 120. The superheated steam sucked into the compressor 110 is adiabatically compressed in a compression section (not shown) and supplied to an outdoor heat exchanger (in this case, a condenser) 130 as a high-pressure gas refrigerant having a high degree of superheat.

  The high-pressure gas refrigerant supplied to the outdoor heat exchanger 130 is cooled by heat exchange with the outside air, and becomes saturated liquid with latent heat of condensation while maintaining a constant pressure. Further, sensible heat is released to become supercooled liquid, which is once stored in the receiver tank 140 and then supplied to the indoor unit 200 via the liquid side refrigerant pipes 161 and 201.

  The supercooled liquid supplied to the indoor unit 200 becomes a low-temperature and low-pressure refrigerant liquid (wet steam) in the electronic expansion valve 220 and flows to the indoor heat exchanger (in this case, the evaporator) 210. The wet steam becomes dry steam by heat exchange with the outside air in the indoor heat exchanger 210.

  And it becomes superheated steam of about 5-10K by sensible heat, and is suck | inhaled by the compressor 110 through the gas side refrigerant | coolant piping 202,162, the four-way valve 120, and the accumulator 170. FIG. During the heating operation, the four-way valve 120 is switched, the indoor heat exchanger 210 acts as a condenser, and the outdoor heat exchanger 130 acts as an evaporator.

  Assuming that this air conditioner is, for example, a building multi-air conditioner, after the outdoor unit 100 and the indoor unit 200 are connected by piping, when the additional refrigerant is filled in the piping from the refrigerant cylinder 300, in the present invention, the outdoor unit A refrigerant charging kit 310 having a flow rate adjustment valve (in this example, an electromagnetic valve) 311 controlled by the control unit 180 is used.

  In charging the additional refrigerant in the present invention, as control parameters, the discharge-side superheat degree of the compressor 110 is SH1, its threshold is T1, the suction-side superheat degree of the compressor 110 is SH2, its threshold is T2, and the compressor 110 The discharge tank pressure is HP, its lower and upper thresholds are P1 and P2, the suction pressure of the compressor 110 is LP, its lower and upper thresholds are P3 and P4, and a receiver tank that is detected by the liquid level detection means 150 The liquid level in 140 is RL, and the predetermined appropriate liquid level in receiver tank 140 is M.

  First, the inlet side of the electromagnetic valve 311 and the refrigerant cylinder 300 are connected by the charging hose 321, and the outlet side of the electromagnetic valve 311 and the three-way valve 163 are connected by the charging hose 322. Further, the signal input port of the refrigerant filling kit 310 and the signal output port of the outdoor unit control unit 180 are connected via a signal cable 323.

  A valve (not shown) of the refrigerant cylinder 300 is opened freely, and after evacuating the piping system on the indoor unit 200 side, the three-way valve 163 is fully opened, and the cooling operation is performed only with the refrigerant for the initial charge of the outdoor unit. Start.

  With reference to the flowchart of FIG. 2, after the cooling operation is started, the outdoor unit control unit 180 determines whether or not the system is in an appropriate state. As parameters for determining this, the discharge-side superheat degree SH1 and the suction-side superheat degree SH2 of the compressor 110 are used.

The discharge-side superheat degree SH1 is obtained by the following equation, assuming that the discharge refrigerant temperature value (average value) detected by the high-pressure side temperature sensor 101 is TAVE and the high-pressure saturation temperature value obtained from the high-pressure side pressure sensor 103 is TSHP. It is done.
SH1 = TAVE-TSHP

Further, assuming that the suction refrigerant temperature value (average value) detected by the low-pressure side temperature sensor 102 is TSUC and the low-pressure saturation temperature value obtained from the low-pressure side pressure sensor 104 is TSLP, the suction-side superheat degree SH2 is expressed by the following equation: Is required.
SH2 = TSUC-TSLP

  The outdoor unit control unit 180 monitors whether each of the conditions of SH1 ≧ T1 and SH2 ≧ T2 (hereinafter sometimes referred to as the first condition) is satisfied, and when the first condition is satisfied, the system is appropriately Therefore, it is determined that the state has been reached, and an open signal is output to the electromagnetic valve 311 to fill the refrigerant in the refrigerant cylinder 300 from the gas side refrigerant pipe 162 side. In the first condition, “≧” may be “>”.

  The threshold value T1 of the discharge side superheat degree SH1 and the threshold value T2 of the suction side superheat degree SH2 are threshold values for maintaining the safety of the compressor 110 (preventing damage due to liquid back), and may be set arbitrarily. Even if the first condition is satisfied, the outdoor unit control unit 180 outputs a close signal to the electromagnetic valve 311 when SH1 <T1 and / or SH2 <T2.

  While the first condition is satisfied and the additional refrigerant is being charged, the outdoor unit control unit 180 sets the discharge side pressure HP, the suction side pressure LP of the compressor 110 and the liquid level in the receiver tank 140 to RL. Is monitored, and it is determined whether or not each of the conditions of P1 <HP <P2, P3 <LP <P4, RL ≧ M (hereinafter sometimes referred to as a second condition) is satisfied. In the second condition, “<” may be “≦” and “≧” may be “>”.

  When the second condition is satisfied, the outdoor unit control unit 180 determines that an appropriate refrigerant is filled in the system, outputs a close signal to the electromagnetic valve 311, and finishes the refrigerant filling from the refrigerant cylinder 300. Thus, according to the present invention, the refrigerant filling pace is automatically adjusted.

  FIG. 3 shows a Mollier diagram when the additional refrigerant is charged. Since the additional refrigerant is charged from the three-way valve 163 provided in the gas side refrigerant pipe 162, the liquid refrigerant to be filled is directly sucked into the compressor 110.

  The fact that the discharge side superheat degree SH1 and the suction side superheat degree SH2 are small means that the liquid refrigerant has returned too much to the compressor 110. Therefore, in the present invention, the SH1 and SH2 are monitored, and the Mollier line of FIG. In the figure, the charging / discharging pace of the additional refrigerant is adjusted by controlling the opening / closing of the electromagnetic valve 311 so that the degree of superheat a is maintained above a certain level.

On the other hand, the indoor unit 200 uses an inlet temperature sensor 231 and an outlet temperature sensor 232 provided on the low-pressure two-phase refrigerant inflow side, and uses the refrigerant temperature value detected by the inlet temperature sensor 231 as the evaporation temperature to determine the degree of superheat ( SH) control is performed and reflected in the opening degree of the electronic expansion valve 220.

The superheat degree SH3 of the indoor unit 200 is expressed by the following equation, where TH1 is the refrigerant temperature value detected by the inlet temperature sensor 231 and THM is the refrigerant temperature value detected by the intermediate temperature sensor 232.
SH3 = THM-TH1

  In FIG. 1, the liquid refrigerant condensed in the outdoor heat exchanger 130 begins to gradually accumulate from the electronic expansion valve 220 side of the indoor unit 200, and after the liquid side refrigerant pipes 161 and 201 are filled with the liquid refrigerant, the receiver It collects in the tank 140. The appropriate liquid level M in the receiver tank 140 is the amount of refrigerant necessary to establish a refrigeration cycle in various operating states.

Next, a method for determining the additional refrigerant charge amount will be described. Accurate control of high and low pressure values is required to accurately determine the filling amount in the connecting pipe. This is because the refrigerant state needs to fall within a value close to a predetermined density [kg / m ³ ] that is assumed.

  Therefore, the discharge side pressure HP, which is a high pressure value, is controlled by the number of revolutions of the inverter fan 131 attached to the outdoor heat exchanger 130, and the suction side pressure LP, which is a low pressure value, is controlled by a compressor by inverter control. The rotation is performed at 110 rpm.

  In the inverter fan 131, control is performed by calculating a high pressure value as a control target from the outside air temperature. In the compressor 110, control is performed so as to change the rotation speed of the compressor to a predetermined low pressure value.

  At this time, it is assumed that the discharge-side pressure HP and the suction-side pressure LP fall within the above-described determination criteria (P1 <HP <P2, P3 <LP <P4). The thresholds P1 to P4 are based on the high and low pressure values used for compressor control and fan control, and the values are changed according to the rise and fall of the outside air temperature. That is, as shown in FIG. 3, the target Mollier diagram is changed according to the outside air temperature.

The schematic diagram which shows the whole structure of the air conditioner by the freezing apparatus of this invention. The flowchart for operation | movement explanation at the time of additional refrigerant filling. The Mollier diagram for operation | movement explanation at the time of additional refrigerant filling.

Explanation of symbols

DESCRIPTION OF SYMBOLS 100 Outdoor unit 110 Compressor 120 Four-way valve 130 Outdoor heat exchanger 140 Receiver tank 150 Liquid level detection means 161 Liquid side refrigerant pipe 162 Gas side refrigerant pipe 163 Three-way valve (flow-path switching valve)
170 accumulator 180 outdoor unit control unit 200 indoor unit 201 liquid side refrigerant pipe 202 gas side refrigerant pipe 210 indoor heat exchanger 220 electronic expansion valve 300 refrigerant cylinder 310 refrigerant filling kit 311 solenoid valve (flow rate adjusting valve)

Claims (7)

In contrast to the heat source side unit including the compressor, the heat source side heat exchanger, and the outdoor unit controller, the usage side unit including the usage side heat exchanger and the refrigerant expansion means is connected via the liquid side refrigerant pipe and the gas side refrigerant pipe. A receiver tank having a liquid level detecting means is provided in the liquid side refrigerant pipe in the heat source side unit and connected to the gas side refrigerant pipe in the heat source side unit. In a refrigeration apparatus equipped with a valve,
Having a flow rate adjusting valve interposed between the refrigerant cylinder and the flow path switching valve at the time of additional charging of the refrigerant and controlled to be opened and closed by the outdoor unit control unit;
The discharge side superheat degree of the compressor is SH1, its threshold is T1, the suction side superheat degree of the compressor is SH2, and its threshold is T2.
In the additional refrigerant charging mode, the outdoor unit controller satisfies the conditions of SH1 ≧ T1 (or SH1> T1) and SH2 ≧ T2 (or SH2> T2) with the refrigeration apparatus in the cooling operation. A refrigerating apparatus which outputs an open signal to the flow rate adjusting valve to fill the refrigerant.   The outdoor unit control unit outputs a close signal to the flow rate adjusting valve to stop refrigerant charging when SH1 <T1 (or SH1 ≦ T1) and / or SH2 <T2 (or SH2 ≦ T2). The refrigeration apparatus according to claim 1. The discharge side pressure of the compressor is detected by HP, its lower and upper thresholds are P1, P2, the suction pressure of the compressor is LP, its lower and upper thresholds are P3, P4, and detected by the liquid level detecting means. The liquid level in the receiver tank is RL, the predetermined appropriate liquid level in the receiver tank is M,
While the refrigerant is being charged, the outdoor unit control unit is configured such that P1 <HP <P2 (or P1 ≦ HP ≦ P2), P3 <LP <P4 (or P3 ≦ LP ≦ P4), RL ≧ M (or RL> M) 2. The refrigeration apparatus according to claim 1, wherein when both of the above conditions are satisfied, a closing signal is output to the flow rate adjusting valve to end the refrigerant charging.   4. The discharge side superheat degree SH1 is obtained from a discharge refrigerant temperature and a high pressure saturation temperature of the compressor, and the suction side superheat degree SH2 is obtained from an intake refrigerant temperature and a low pressure saturation temperature of the compressor. The refrigeration apparatus according to claim 1.   In the use side unit, superheat degree control is performed based on temperatures detected from an inlet temperature sensor provided on the low pressure two-phase refrigerant inflow side of the use side heat exchanger and an outlet temperature sensor of the use side heat exchanger. The refrigeration apparatus according to any one of claims 1 to 4, wherein:   The flow control valve is controlled to be opened and closed by the outdoor unit controller according to claim 1, and is connected between the refrigerant cylinder and the flow path switching valve via a charging hose when the refrigerant is additionally charged. Refrigerant additional filling kit. In contrast to the heat source side unit including the compressor, the heat source side heat exchanger, and the outdoor unit controller, the usage side unit including the usage side heat exchanger and the refrigerant expansion means is connected via the liquid side refrigerant pipe and the gas side refrigerant pipe. A receiver tank having a liquid level detecting means is provided in the liquid side refrigerant pipe in the heat source side unit and connected to the gas side refrigerant pipe in the heat source side unit. In the refrigerant additional charging method of the refrigeration apparatus having a valve,
The discharge side superheat degree of the compressor is SH1, its threshold is T1, the suction side superheat degree of the compressor is SH2, its threshold is T2, the discharge side pressure of the compressor is HP, and its lower and upper thresholds are P1. , P2, the suction side pressure of the compressor is LP, the lower and upper thresholds are P3 and P4, the liquid level in the receiver tank detected by the liquid level detecting means is RL, and the predetermined level in the receiver tank is Assuming that the appropriate liquid level is M,
The refrigerant pipe on the indoor unit side is evacuated in a state where the refrigerant cylinder is connected to the flow path switching valve via a flow rate control valve whose opening and closing is controlled by the outdoor unit control unit, and then the flow path switching valve and the Open the refrigerant cylinder valve, close the flow rate adjustment valve, and cool the refrigeration system with only the refrigerant for the initial charge,
When both the conditions of SH1 ≧ T1 (or SH1> T1) and SH2 ≧ T2 (or SH2> T2) are satisfied, an open signal is output to the flow rate adjusting valve so that the refrigerant in the refrigerant cylinder is Fill from the refrigerant piping side,
Thereafter, when the conditions of P1 <HP <P2 (or P1 ≦ HP ≦ P2), P3 <LP <P4 (or P3 ≦ LP ≦ P4), and RL ≧ M (or RL> M) are all satisfied A refrigerant additional charging method for a refrigeration apparatus, wherein a closing signal is output to a flow rate adjusting valve to end the refrigerant charging from the refrigerant cylinder.

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