Daewoo FRS(N)-U20IA, Service Manual

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77
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 (drier part) with a nipper and then cut low pressure side.
1. Removal of residual
refrigerant.
Precautions Items
10-3. Practical Work for Heavy Repair
* When replacing a drier:
Weld
①
and
②
parts by blowing nitrogen (0.1~0.2kg/cm2) to high
pressure side after assembling a drier.
* 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.
2. Nitrogen blowing
welding.
※ ※ ※ ※
KEYPOINTING
Welding without nitrogen blowing produces oxidized scales inside
a pipe, Which affect on performance and reliability of a product.
Process tube
Compressor
Evaporator
Dryer
High Pressure side
Low pressure
side
Suction tube
Discharge tube
Condenser
Hot Pipe
Process tube
Compressor
Evaporator
Dryer
High Pressure side
Low pressure
side
①
Condenser
②
③
④
Hot Pipe