Friedrich Q Series Service & Parts Manual page 51

COMPONENT TESTING
Compressor Replacement -Special Procedure in Case of Compressor Burnout
WARNING
HIGH PRESSURE HAZARD
Sealed Refrigeration System contains refrigerant
and oil under high pressure.
Proper safety procedures must be followed,
and proper protective clothing must be worn
when working with refrigerants.
Failure to follow these procedures could
result in serious injury or death.
WARNING
EXPLOSION HAZARD
The use of nitrogen requires a pressure
regulator. Follow all safety procedures and
wear protective safety clothing etc.
Failure to follow proper safety procedures
could result in serious injury or death.
WARNING
ELECTRIC SHOCK HAZARD
Turn off electric power before service or
installation. Extreme care must be used, if it
becomes necessary to work on equipment with
power applied.
Failure to do so could result in serious injury or
death.
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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. Use approved flushing agent to remove all
contamination from system. Inspect suction and discharge line for
carbon deposits. Remove and clean if necessary. Ensure all acid is
neutralized.
4. Reassemble the system, including new drier strainer and capillary
tube.
5. Pressurize with a combination of R-410A and nitrogen and leak test
all connections with an electronic or Halide leak detector. Recover
refrigerant and repair any leaks found.
5a. If leak detector is unavailable remove all refrigerant from system
and pressurize with nitrogen to 350 psi. Check that system holds
pressure.
Repeat Step 5 to insure no more leaks are present
6. Evacuate the system with a good vacuum pump capable of a final
vacuum of 200 microns or less. The system should be evacuated
through both liquid line and suction line gauge ports. While the unit
is being evacuated, seal all openings on the defective compressor.
Compressor manufacturers will void warranties on units received not
properly sealed. Do not distort the manufacturers tube connections.
7. Recharge the system with the correct amount of refrigerant. The
proper refrigerant charge will be found on the unit rating plate. The
use of an accurate measuring device, such as a charging cylinder,
electronic scales or similar device is necessary.
ROTARY AND SCROLL COMPRESSOR SPECIAL TROUBLESHOOTING
AND SERVICE
Troubleshooting and servicing rotary compres-sors is basically
the same as on the reciprocating compressor with only one main
exception:
NEVER, under any circumstances, liquid charge a rotary-compressor
through the LOW side. Doing so would cause permanent damage to
the new compressor. Use a charging adapter.