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19
AIR PURGING
The purpose of air purging is to get rid of moisture
and air in the system, otherwise moisture and air
may cause ineffectiveness of the compressor which
directly affects the cooling and heating capacity.
After tightening the flare nuts between the indoor
and the outdoor units.
Remove a blank cap of a three-way valve by using a
torque wrench. Check if both high pressure and low
pressure valves are in closed condition.
Remove the nut of the service port.
Connect a gauge into the service port and a vacuum
pump.
Vacuum indoor unit and connecting pipe until the gauge
indicates at 30 inches mercury pressure.
Remove gauge. Tighten up the nut of the service port.
Use a hexagonal wrench to open both high pressure
and low pressure valves to the end (counter clockwise).
Tighten the blank cap of the three-way valve.
GAS LEAKING CHECK
Check leakage by apply soapsuds to every
connection and inspect carefully. After checking,
wipe them off completely.
Cover indoor unit joint with pipe insulation and
plastic bands to prevent condensation at joints.
1.
PURGING BY USING VACUUM
AIR PURGING AND CHECK FOR PIPE LEAKAGE
INSTALLATION INSTRUCTIONS