Airwell YCV280, Installation And Maintenance Instructions Manual

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welding
adhesive tape
flat
When welding the valve and the pipes, use the wet cloth to cool down the valve
and the pipes.
The refrigerant pipe should be clean. The nitrogen should flow under the pressure of about 0.02Mpa
and when charging the nitrogen, stop up the end of the pipe by hand to enhance the pressure in the
pipe, then loose the hand (meanwhile stop up the other end).
source valve
1st side
2nd side
hand
0.02MPa
3. Leakage testing
Charge nitrogen(to test the leakage condition)
To prevent the nitrogen into outdoor system, charge nitrogen to the indoor respectively. Connect the
connection pipe to checking joint of the indoor gas pipe stop valve, and seal all the other joints except
for outdoor's, charge the nitrogen, the gas pressure should be 40Kf/cm2.
1) The outdoor unit has been executed the leakage test in the factory. After connecting the distributing
pipe, execute the leakage test from the outdoor check valve and the indoor. Besides, while testing, the
valves should be close.
2) Refer to the below figure to charge the nitrogen into the unit to take a test. Never use the chlorin,
oxygen, flammable gas in the leakage test. Apply pressure both on the gas pipe and the liquid pipe.
3) Apply the pressure step by step to the target pressure.
a. Apply the pressure to 0.5MPa for more than 5 minutes, confirm if pressure goes down.
b. Apply the pressure to 1.5MPa for more than 5 minutes, confirm if pressure goes down.
c. Apply the pressure to the target pressure (4.05MPa), record the temp. and the pressure.
d. Leave it at 4.05MPa for over 1 day, if pressure does not go down, the test is passed. Meanwhile,
when the temp. changes for 1degree, pressure will change 0.01MPa as well. Correct the pressure.
Protect the pipe end against the water, impurity into the pipes (welding after being flat, or being sealed
with adhesive tape).
When connecting the pipes, close the valves fully.
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