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Refrigerant Leak Test Procedure
Refrigeration Maintenance and Service Operations
CRR-20 & CRR-40, September 1999
To check compressor oil level with an ambient air
temperature below 10 C (50 F)
With the evaporator temperature below 10 C (50 F), initiate a
Manual Defrost to operate the unit through a complete
DEFROST CYCLE. After completing the defrost cycle, oper-
ate the unit on COOL for a few minutes. After 2 to 3 minutes,
observe the oil level. The oil should be 1/2 to 3/4 up in the
sight glass.
If the container is empty, you can operate the unit on the
heat cycle instead of the defrost cycle.
Adding Compressor Oil
1.
Install gauge manifold set (refer to “Gauge Manifold Set
Attachment and Purging”). Pump the compressor down
(refer to “Low Side Pump Down”).
2.
After stopping the compressor, adjust the low side pres-
sure to to 21 kPa, 0.21 bar, 3 psig using the service gauge
set. (Pressure measured at the suction line service port.)
3.
Remove the cap from oil pressure fitting on oil pump.
4.
Using a commercial hand pump, force oil in through the
oil pressure fitting. Slowly add oil and allow 5 to 10 min-
utes for the oil to flow down through the compressor into
the sump. Add Polyol Ester oil, P/N 203-433 ONLY!
5.
When the compressor oil sight glass is 1/2 to 3/4 full,
remove hand pump and replace the cap on the oil pressure
fitting.
6.
Open the compressor suction service valve (or receiver
tank outlet valve) and operate the unit. Recheck the
refrigerant charge level and the oil level before returning
the unit to service.
Removing Excess Compressor Oil
1.
Install an access valve actuator on the oil pressure fitting.
2.
Operate the unit and remove oil while watching the level
in the compressor sight glass.
NOTE: Heavy foaming of the oil as it leaves the
compressor may indicate an excess of refriger-
ant in the oil. Remove the access valve actuator
and operate the system for 15 minutes to ensure
warm sump. Then recheck the oil level.
3.
When the compressor oil sight glass is 1/2 to 3/4 full,
remove access valve and replace the cap on the oil pres-
sure fitting.
4.
Operate the unit and recheck the refrigerant charge level
and the oil level before returning the unit to service.
Refrigerant Leak Test Procedure
Use a reliable Halogen leak detector such as model H10G, P/N
204-712 or 204-756 (portable), to leak test the refrigeration
system. Inspect carefully for signs of compressor oil leakage
which is the first sign of a leak in the refrigeration system.
NOTE: Due to environmental concerns and personal
safety, the use of a Halide torch is no longer recom-
mended.
If refrigerant has leaked or been removed from the unit:
1.
Check entire system for possible component damage and
refrigerant oil loss.
2.
Attach gauge manifold set (refer to “Gauge Manifold Set
Attachment and Purging” for proper procedures).
3.
Attach refrigerant bottle charging hose to center of gauge
manifold and purge charging hose of air.
4.
Pressurize the system with refrigerant (GAS ONLY) until
345 kPa, 3.45 bar, 50 psig vapor pressure is achieved.
5.
Leak check the system with an electronic leak detector to
inspect all joints and connections. (Use soap solution as
an alternative test component.)
If no leaks are found but the system has lost its refrig-
erant charge, proceed to the next step.
6.
Close both hand valves on gauge manifold (front seated).
7.
Disconnect the refrigerant charging hose.
Testing for Refrigerant Leaks
Содержание CRR-20
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