Thermo King CRR-20, Руководство по обслуживанию

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6-2 Compressor Service Valves Refrigeration Maintenance and Service Operations
CRR-20 & CRR-40, September 1999
Because vacuum pump oils are highly refined to obtain
low vacuums, failure to follow these recommendations may
result in acidic conditions that will destroy the pump.
System Cleanup
Cleanup devices such as suction line filters and compressor oil
filters may be used if they are properly cleaned and new filters
and cartridges are used. All standard petroleum and synthetic
compressor oils must be removed to prevent the contamination
of R-134a systems.
Refrigerant Recovery
Use only refrigerant recovery equipment approved for and
dedicated to R-134a recovery.
Compressor Oil Acid Test
Perform an oil acid test (oil test kit P/N 203-457) whenever a
unit has a substantial refrigerant loss, a noisy compressor or
dark/dirty oil.
Compressor Discharge and Suction Service
Valves
The discharge and suction valves isolate the compressor from
the high and low sides of the refrigeration system for system
diagnosis, service and repair.
NOTE: The only maintenance possible on the dis-
charge or suction service valve is to periodically
tighten the packing nut or to replace the packing.
The valves are a permanently assembled unit and
must be replaced in total if defective.
• Back Seated: Normal operation position.
• Open to Service Port: Position for servicing.
• Front Seated: To check or remove compressor.
WARNING: Do not start unit with discharge valve in
FRONT SEATED position.
Service Valve Open to Port
1. 1/2 Turn In
Service Valve Back Seated
1. Full Counterclockwise
Service Valve Front Seated
1. Full Clockwise