Household Unit Technical Service Manual
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4.4 Care and Maintenance
4.4.1 Maintenance of Heat Exchanger
The heat exchanger of outdoor unit shall be periodically cleaned every two months the shortest. You may
use vacuum cleaner and nylon brush to remove the dust and foreign particles on the surface of heat
exchanger. You may use compressed air, if available, to purge off the dust on the surface of the heat
exchanger. Never use tap water to wash.
4.4.2
Maintenance at the Start of Service Season
1) Check the air inlet and outlet of the indoor and outdoor units for any block.
2) Check if the earthing of the unit is secure and in good condition.
3) Check if the cable connection is in good condition.
4.4.3
Maintenance at the End of Service Season
1) Clean the body of outdoor unit and clear off the dust and foreign matters.
2) Take proper protection of the body of outdoor unit.
3) Disconnect the power supply of outdoor unit.
4.4.4 Cautions
When performing the airtight and leakage test, never mix the oxygen, acetylene or other dangerous gas into
the refrigerating loop. To avoid danger, it is best to use nitrogen or refrigerant to do this test.
4.5 Important Repairs
4.5.1 Add compressor oil
Operating Steps:
1
）
Collect the Freon under COOL mode operation. Close the gas valve and liquid valve tightly.
2
）
Cut off the connection pipe (large diameter) and valve.
3
）
Add compressor oil into the connection pipe.
4
）
Reweld the connection pipe and valve properly.
5
）
Vacuum and maintain the pressure for 30 minutes.
6
）
Open the gas valve and liquid valve.
7
）
Start the unit to run.
4.5.2 Replace the compressor
Operating Steps:
(1)
Firstly, cut off the power supply to the outdoor unit. For correct reconnection of the cables after repair,
each cable and its corresponding terminal shall be properly identified when removing the power cables
of the compressor.
(2)
Loosen the support fixing the compressor.
(3)
Firstly, melt the soldering filler at the compressor exhaust port and slightly open the exhaust pipe to
make it fall out from the compressor exhaust port.
(4)
Melt the soldering filler at the compressor suction port and gently shake the compressor to make the
