Midea MPM1-10CEN1-BB6, Техническое и сервисное руководство

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Basic test procedure
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ƒ 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.
ƒ Recover all refrigerant and oil from the system.
ƒ Remove compressor, capillary tube and filter drier from the system.
ƒ 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.
ƒ Reassemble the system, including new drier strainer and capillary tube.
ƒ 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.
ƒ Because of the spinning motion of the rotary, the mounts are critical. If vibration is
present, check the mounts carefully.
ƒ 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.
9.2.6 Refrigerant charge
ƒ The refrigerant charge is extremely critical. It must be measured charge carefully - as
exact as possible to the nameplate charge.
ƒ 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.
9.3 Fan motor
A single phase permanent split capacitor motor is used to drive the evaporator blower and
condenser fan. A self-resetting overload is located inside the motor to protect against high
temperature and high amperage conditions.
9.3.1 Fan motor test
ƒ
Determine that capacitor is serviceable.
ƒ
Disconnect fan motor wires from fan speed switch or system switch.
ƒ
Apply "live" test cord probes on black wire and common terminal of capacitor. Motor
should run at high speed.
ƒ
Apply "live" test cord probes on red wire and common terminal of capacitor. Motor should
run at low speed.