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!
WARNING
To avoid risk of electrical shock that can cause death or severe personal injury,
disconnect unit from power before servicing unless tests require power.
10. Cooling Cycle Heavy Repair
10-3. Practical Work for Heavy Repair
Items
Precautions
1. Removal of
residual refrigerant
1) Remove residual refrigerant more than 5 minutes later after turning off the refrigerator.
(If not, compressor oil may leak inside.)
2) Remove retained refrigerant slowly by cutting first high pressure side (dryer part) with a
nipper and then cut low pressure side.
2. Nitrogen
blowing
welding
When replacing a dryer :
Weld
①
and
②
parts by blowing nitrogen (0.1~0.2kg/cm2) to high pressure side after
assembling a dryer.
When replacing a compressor :
Weld
③
and
④
parts by blowing nitrogen to the low pressure side.
※
Note) For other parts, nitrogen blowing is not necessary because it does not
produce oxidized scales inside pipe because of its short welding time.
■
KEYPOINTING
■
Welding without nitrogen blowing produces oxidized scales inside a pipe,
which affect on performance and reliability of a product.
