Thermo King CRR-40 119, Руководство пользователя

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Refrigeration Maintenance and Service Operations
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Vacuum Pump
A two-stage (P/N 204-725), three-stage or
five-stage pump is recommended for evacuation.
Purging the system with dry nitrogen is
recommended before evacuation. Because
residual refrigerant may be present in used
vacuum pumps, a new vacuum pump should be
used and dedicated strictly as an R-134a
refrigerant pump. Use only recommended vacuum
pump oils and change oil after every major
evacuation.
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
discharge 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.
1. Full Counterclockwise
Figure 30: Service Valve Back Seated
1. 1/2 Turn In
Figure 31: Service Valve Open to Port
1. Full Clockwise
Figure 32: Service Valve Front Seated
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