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Evacuation and Refrigerant Charge
Tools and Instruments - Vacuum pump, High Pressure Compound Gauge, Low Pressure Compound
Gauge, Refrigerant cylinder with Sufficient R410A, Weighing Scale, Refrigerating Oil (if Required),
Charging Hoses, and Other General Piping Tools.
Preparation - Confirm the required amount of refrigerant, referring to Table 2. Arrange piping connection
work for evacuation and refrigerant charge, as shown in Fig. 13.
1. Check to ensure that the stop valves have been closed.
2. Attach the connection pipes to the stop valves.
3. Connect the Cooling unit and the condensing unit by refrigerant piping.
4. Charge air or nonflammable gas (other than oxygen or poisonous gas) from the charge port of the
liquid stop valve, and perform airtight tests...Airtight Test Pressure: 42kg/cm
of E406DH, E506DH, E626DH and E856DH Compressor.
Evacuation Procedures - Before charging refrigerant, the entire refrigeration cycle must be completely
evacuated and dehydrated. Connect the high pressure compound gauge to the high pressure check joint
at the compressor discharge side, and the low pressure compound gauge to the low pressure check joint
at the compressor suction side.
1. Connect the vacuum pump to the service joint of the unit liquid stop valve.
2. Operate the vacuum pump to perform primary evacuation of the connection piping and the cooling
unit.
3. Slowly open the liquid outlet stop valve and the gas inlet stop valve. Ensure that the unit is being
evacuated by checking both gauges.
4. Continue vacuum pump operation until the pressure indication on the gauges shows –0.1 Mpa
(-756 mmHg).
5. Turn off the vacuum pump, wait for approximately 5 minutes and make sure the pressure no longer
riser. And then close the vacuum pump connection line.
Refrigerant Charge –This unit has been charged with refrigerant. If the pipe is longer than the standard
setting for refrigerant, recharge proper amount of refrigerant at the installation location.
1. Change the vacuum pump with the refrigerant charging cylinder on the weighing scale.
2. Purge air from the refrigerant charging cylinder connection line.
3. Charge liquid refrigerant as required into the refrigeration cycle by weighing the refrigerant charging
cylinder.
4. After all evacuation and charging work, tighten the cap nuts for the unit stop valves.
5. Be sure to conduct the leakage test.
NOTES:
1. The above evacuation and charging procedures should be accomplished for both refrigeration cycles
of the dual circuited models.
2. A gauge manifold or equivalent piping connected with a vacuum pump and a refrigerant charging
cylinder is recommended for rapid evacuation and charging work.
3. When charging by weight is ceased due to high ambient temperature, close the liquid outlet stop valve.
Then operate the entire system at the stage of initial start-up. For dual-circuited models, suspend the
other circuit operation by blocking the control circuit.
․ ․ ․ ․ This air conditioner uses refrigerant R410A, use only the manifold gage and
the charging hose exclusive for R410A.
․ ․ ․ ․ If the pressure does not drop to –0.1Mpa after vacuuming for an hour, there
may be leakage or moisture in the pipes.
․ ․ ․ ․ Precautions for new refrigerants R410A is non-azeotrope refrigerant.
Therefore, when the refrigerant leaks, its component's weight percentage
will change. Instead of recharging refrigerant, we should process the
system all over again.
REFRIGERANT PIPING
2
G for Refrigeration Cycle
22
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