Magic Chef MCSR-6085W, Инструкция по эксплуатации

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compressor is generally controlled by a thermostat . When the temperature in the
refrigerator reaches its desired value, the thermostat will shut down the compressor
automatically. Never take this normal operation as a trouble, care should be taken to
differentiate it from other real troubles in servicing.
D. Compressor won ‹t start In case the compressor cannot be started, you must find
out the origins of this trouble through checkup step by step, because probably there are
many causes, including those electrical and mechanical.
1) Inspect the power supply to see whether it is connected to the compressor circuit.
Analysis of Trouble
In case the compressor cannot be started, this will generally exhibit in
the power supply circuit, for instance, power failure, poor contact of switch,
and blown fuse. Make a comprehensive analysis of these phenomena, fine
out its real cause and take correct measures to remove this trouble.
Remedy
a) Check the input power circuit to see whether where is voltage of the power supply,
namely, the circuit which is connected to the knife switch. This can be determined with
an avometer or a test pencil. If a blown fuse is found, ascertain and remove its cause,
then replace it with a new one of the same specifications.
b) Check the compressor accessories, including its thermal protector and relay. In case
the thermal protector is damaged, the compressor cannot be powered on. If the relay
is out of order, the motor will not run and hum sound can be heard from it after the
compressor is turned on, in that case, shut it down immediately, otherwise, the motor
windings will be burned out in case this condition lasts longer.
c) Check the relay contacts and plugs to see if they are perfect and work reliably. Poor
contact may cause the motor not running or humming.
2) Check the circuit voltage to see whether it is normal. Analysis of trouble If the circuit
voltage is obviously lower than its rated value, it will be difficult to start the motor, and
a hum sound can be heard from it. Remedy Measure the voltage with a voltmeter, if it
is really too low, give directions to the user for buying a stabilizer so as to step up the
voltage, thus normal operation can be achieved.
3) Check the thermal relay to see whether its contacts are closed. Analysis of Trouble The
contacts of thermal relay sometimes may be open due to the leakage of temperature
air is higher gas discharge pressure, higher discharged gas temperature (the gas discharge
tubing is considerably hot when you feel it with your hand), and poorer refrigerating
effect. Furthermore, the gas discharge pressure will exceed its normal value when the
compressor has run for a period not too long, thus making the protective relay actuate
and bring to a stoppage. Remedy Check up how the air has been left in the refrigerating
system. Generally, there are two possibilities: one is that the air has been sucked into the
system when repairing due to carelessness, or it has not been purged out totally when
evacuating the system; the other is that there are leak points at the low pressure end
of the refrigerating system. Leak points appear mostly in those low temperature parts
or assemblies, because the evaporation temperature is lower for such low temperature
devices, especially at the low pressure end, it is easier for the air goes into the system.
Once it has been ascertained that air does exist in the system, you have to open the
tubing, re-evacuate it and then charge it with refrigerant.
2) Stoppage due to electric troubles
a) Thermostat is out of control Analysis of Trouble In case the thermostat does not work
in its good order or its temperature sensor has not been installed properly, frequent
stoppage is also likely to occur. Remedy Try to adjust the temperature sensor›s position
until the compressor can be started and stopped normally. If this cannot be achieved,
and the stoppage still occurs repeatedly, it is most likely that the mechanical parts or
contacts are out of order, disassemble the thermostat, make a thorough checkup and
repair it.
b) Overload of electric motor Analysis of Trouble Probably, too many things have been
put into the refrigerator, and hence the thermal load exceeds its refrigerating capacity ;
or in case the power supply voltage drops considerably, the current flowing through the
motor will increase drastically making the thermal protector actuate and the fuse blown
, and hence the motor stops running. If the motor is still running continuously in such a
case , its windings will be burned out . Remedy Reduce the thermal load, pay attention
to the variation in voltage of the power supply.
c) Abnormal thermal protection
Analysis of Trouble The compressor current is within its normal range, but the thermal
protector actuates repeatedly. Remedy Replace the thermal protector with a new one.
3) Sudden stoppage due to other causes Normal Stoppage Start and stop of the