McQuay 5MDS 50, Руководство по установке

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Installation Manual IM-MDS_(i) 25
LEAKAGE TEST SKETCH
to indoor unit
to indoor unit
nitrogen
LO
outdoor
unit
ball valve
ball valve
liquid pipe
gas pipe
HI
service port
pressure gauge
8.0 Air Leakage Test, Vacuum and Refrigerant Charge
8.1 Air leakage test

To conduct air leakage test, ensure the ball valve is off.

Refer to the procedure below to avoid polluting the lubricating
oil during the leakage test.
Air leakage testing procedure Remark
Charging Nitrogen gas

Nitrogen gas (For R410A units: 4.15MPa, R22 units: 2.94MPa),
wait for 24 hours. If the pressure is not drop, the units pass the
air tightness testing; if pressure decrease, use soap water to
detect the leakage point.

After charging the nitrogen gas, use soap water on the part of
brazing, flange and connection position to see if there is any
bubble occurred.

After air leakage testing, wipe off the bubbling agent.
Do not use oxygen and other flammable
air to increase the pressure to avoid
explosion
8.2 Vacuum

Ensure the ball valve is off before conducting vacuum.

Vacuum pressure is 650Pa and the time of vacuum is
24 hours.

Do not use refrigerant to vacuum.
8.3 Charging the refrigerant

Charge in additional refrigerant based on the piping length connection.

Additional charge required can be obtained from selection report or calculated manually with the steps as
shown below.
Additional charge amount:
= ∑ Li* Gi
= (Piping Length for 15.88mm X Additional Charge Amount)
+ (Piping Length for 12.7mm X Additional Charge Amount)
+ (Piping Length for 9.52mm X Additional Charge Amount)
+ (Piping Length for 6.35mm X Additional Charge Amount)
Caution that the additional charge amount of different pipe diameter varies base on type of refrigerant.
Pipe Diamater (mm) 6.35 9.52 12.70 15.88 19.05
R22 Additional Charge (g/m) 50 80 120 180 290
Pipe Diamater (mm) 6.35 9.52 12.70 15.88 19.05
R41A additional Charge (g/m) 45 70 120 180 260

Before charging, open the all ball valve.
vacuum
pump
check valve
service port
ball valve
liquid pipe
gas pipe
ball valve
outdoor
unit
compound
pressure gauge
HI
LO
to indoor unit
to indoor unit
VACUUM SKETCH