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Special requirement during service process
：
(a). Duration of from opening of compressor to vacuuming process must be less than 10
minutes, and for other parts not more than 12 minutes.
(b)
．
Vacuuming duration should not loess than 20 minutes.
(c)
．
If refrigerant leakage happens, it need to replace the compressor. Before welding,
dry the cooling system by the nitrogen air.
(d)
．
If the dust blockage happens in cooling system pipe, if can be blow out by the
nitrogen, don’t need to replace the compressor, otherwise the cabinet is no useful
(and the evaporator is no useful).
(e)
．
If ice blockage happens in the system pipe, must replace the compressor.
f
．
Change the dry filter only if the system is opened.
4) Main point of service
：
①
The replaced compressor must return back to the compressor manufacturer to be
treated.
②
The compressor can’t be tested through direct absorbing atmosphere, it will damage
the compressor.
③
If the system pipe is opened for a long time or leakage happens, you can dry the
system by nitrogen during service.
④
All of the welding material must be protected from wet condition. And ensure to use a
little as enough as possible.
⑤
Check the compressor is pressurized or not when opening.
⑦
When storing the R134a refrigerant, must keep it sealed and not touch with
atmosphere directly.
11. The performance testing requirement after service:
After completing the service, normally need to be done test running for 1-2days. When
proved to be safely and good cooling performance, then move to the customer or user. During
test running, we suggest that you can do following item:
1)
、
Insulation and safety
：
Before plugging in, use the DC 500 meg-ohm meter to measure the insulation
resistance between the live parts and dead metal enclosure, ensure the result is not lower
than 1 meg-ohm.
2)
、
Starting capability
：
The compressor can start smoothly, and can start or stop normally. If the unit can’t
start or stop normally, must find the root cause and delete the cause, then you can
plugging it in to let it run.
3)
、
Cooling performance
：
After running for 24 hours, check that the frost on the surface of the cabinet linear is
oven or not, and there is no frost on the suction pipe.
4)
、
Electrical structure and safety
：
After service, check all of the electrical parts, ensure the connection terminal of
the electrical parts don’t loose and the grounding wire is ok.
