3. Introducing refrigerant charge into high side of the system.
4. Accurately weighing the refrigerant charge actually introduced into the system.
5. Facilities for flowing nitrogen through refrigeration tubing during all brazing processes.
9.2.3 Hermetic compressor
repl
ace
ment.
The following procedure applies when replacing components in the sealed refrigeration circuit or repairing
refrigerant leaks. (Include Compressor, condenser, evaporator, capillary tube, refrigerant leaks, etc.)
1. Recover the refrigerant from the system at the process tube located on the high side of the system by installing
a line tap on the process tube. Apply gauge from process tube to EPA approved
gauges
from process tube to
EPA approved recovery system. Recover CFCs in system to at least 5%.
2. Cut the process tube below pinch off on the suction side of the compressor.
3. Connect the line from the nitrogen tank to the suction process tube.
4. Drift dry nitrogen through the system and unsolder the more distant connection first. (Filter drier, high side
process tube, etc.)
5. Replace inoperative component, and always install a new filter drier. Drift dry nitrogen through the system
when making these connections.
6. Pressurize system to 30 PSIG (2.068 bar) with proper refrigerant and boost refrigerant pressure to 150 PSIG
(10.342 bar) with dry nitrogen.
7. Leak test complete system with electric halogen leak detector, correcting any leaks found.
8. Reduce the system to zero gauge pressure.
9. Connect vacuum pump to high side and low side of system with deep vacuum hoses, or copper tubing. (Do
not use regular hoses.)
10. Evacuate system to maximum absolute holding pressure of 200 microns or less. NOTE: This process can be
speeded up by use of heat lamps, or by breaking the vacuum with refrigerant or dry nitrogen at 5,000 microns.
Pressure system to 5 PSIG (0.344 bar) and leave in system a minimum of 10 minutes. Recover refrigerant, and
proceed with evacuation of a pressure of 200 microns or a minimum of 10%.
11. Break vacuum by charging system from the high side with the correct amount of refrigerant specified.
This will prevent boiling the oil out of the crankcase.
NOTE: If the entire charge will not enter the high side, allow the remainder to enter the low side in
small increments while operating the unit.
12. Restart unit several times after allowing pressures to stabilize. Pinch off process tubes, cut and solder the ends.
Remove pinch off tool, and leak check the process tube ends.
9.2.4 Special procedure in the case of compressor motor burnout.
1. Recover all refrigerant and oil from the system.
2. Remove compressor, capillary tube and filter drier from the system.
3. Flush evaporator condenser and all connecting tubing with dry nitrogen or equivalent, to remove all
contamination from system. Inspect suction and discharge line for carbon deposits. Remove and clean if necessary.
4. Reassemble the system, including new drier strainer and capillary tube.
5. Proceed with processing as outlined under hermetic component replacement.
9.2.5 Rotary compressor special troubleshooting and service
Basically, troubleshooting and servicing rotary compressors is the same as on the reciprocating compressor
with only a few exceptions.
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