10. Evacuate system to maximum absolute holding pres- sure 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 and leave in system a minimum of 10 minutes. Release refriger- ant, and proceed with evacuation of a pressure of 200 microns or less.
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.
SPECIAL PROCEDURE IN THE CASE OF MOTOR COMPRESSOR 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.
ROTARY COMPRESSOR SPECIAL
TROUBLESHOOTING AND SERVICE
Basically, troubleshooting and servicing rotary compres- sors is the same as on the reciprocating compressor with only a few exceptions.
1.Because of the spinning motion of the rotary, the mounts are critical. If vibration is present, check the mounts carefully.
2.The electrical terminals on the rotary are in a differ- ent order than the reciprocating compressors. The terminal markings are on the cover gasket. Use your wiring diagram to insure correct connections.
REFRIGERANT CHARGE
1.The refrigerant charge is extremely critical. Mea- sure charge carefully - as exact as possible to the nameplate charge.
2.The correct method for charging the rotary is to introduce liquid refrigerant into the high side of the system with the unit off. Then start compressor and enter the balance of the charge, gas only, into the low side.
The introduction of liquid into the low side, without the use of a capillary tube, will cause damage to the discharge valve of the rotary compressor.
NOTE: All inoperative compressors returned to Friedrich must have all lines properly plugged with the plugs from the replacement compressor.
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