Haier MRV 5-RC VP1-112B, Service Manual

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86
Nitrogen
Hi handle
Gauge manifold
Hi
To indoor
Lo
Lo handle
1. The outdoor unit has been executed the leakage test in the factory. The pipe should be executed leakage test
individually and forbidden to test after connecting with stop valve.
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 (4.15MPa), record the temp. and the pressure.
d. Leave it at 4.15MPa 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.
e. After confirmation of a~d, if pressure goes down, there is leakage. Check the brazing position, flared position
by laying on the soap. Modify the leakage point and take another leakage test.
4. After leakage test, do execute the evacuation.
B. Leakage test
Evacute at the check valve of liquid stop valve and both sides of the gas stop valve. The oil equalization pipe also
must be vacuum (executed at the oil equalization pipe and check valve respectively).
Operation procedure:
Leakage test passed
Leave it for over 1
hour, vacuum pointer
does not arise.
After reaching -101KPa or
less (below -755mmHg), let
the vacuum pump running
continuously for over 1hour.
Charge refrigerant
Evacuation begins
Check vacuum
Evacuation ends
If vacuum pointer arises, it shows there is water or leakage in the
system, please check and modify it, and then evacuate again.
Because the unit is with refrigerant R410A, the below issues should be paid attention:
• To prevent the oil going into the pipe, please use the special tool for R410A, especially for gauge manifold and
charging hose.
• To prevent the oil going into the refrigerant cycle, please use the anti-counter-flow adapter.
• When maintaining the outdoor, release refrigerant from check valve. When taking vacuum evacuation, set the
relative dip switch. The details refer to Code section.
C. Evacuation