Friedrich SM21J30A4, Руководство по обслуживанию

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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.
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.
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 different
order than the reciprocating compressors. The terminal
markings are on the cover gasket. Use your wiring
diagram to insure correct connections.
REFRIGERANT CHARGING
NOTE: BECAUSE THE RAC SYSTEM IS A SEALED
SYSTEM, SERVICE PROCESS TUBES WILL HAVE TO
BE INSTALLED. FIRST INSTALL A LINE TAP AND
REMOVE REFRIGERANT FROM SYSTEM. MAKE
NECESSARY SEALED SYSTEM REPAIRS AND
VACUUM SYSTEM. CRIMP PROCESS TUBE LINE AND
SOLDER END SHUT. DO NOT LEAVE A SERVICE
VALVE IN THE SEALED SYSTEM.
Proper refrigerant charge is essential to proper unit
operation. Operating a unit with an improper refrigerant
charge will result in reduced performance (capacity) and/or
efficiency. Accordingly, the use of proper charging methods
during servicing will insure that the unit is functioning as
designed and that its compressor will not be damaged.
Too much refrigerant (overcharge) in the system is just as
bad (if not worse) than not enough refrigerant
(undercharge). They both can be the source of certain
compressor failures if they remain uncorrected for any
period of time. Quite often, other problems (such as low air
HERMETIC COMPONENT REPLACEMENT
The following procedure applies when replacing components
in the sealed refrigeration circuit or repairing refrigerant leaks.
(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 CFC's 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 un-solder 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 with proper refrigerant
and boost refrigerant pressure to 150 PSIG 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 and leave in
system a minimum of 10 minutes. Release refrigerant,
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.