Magic Chef MCSR-6085W, Instruction Manual

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and cause the shaft to be seized. Copper plating may also result in seizing of shaft.
b) Seizing of piston This is caused by too small fit clearance between the piston and
cylinder or expansion due to heat. Judgement of seizing shaft and piston: After the
refrigerator has been powered on, the compressor will not start and run, but a slight
hum sound can be heard, and several seconds later, thermal protective relay will actuate
and make the contacts open; this process will occur repeatedly, but the compressor
cannot be started.
E. Compressor won›t stop Sometimes, the compressor will run continuously(for several
hours or run without end), If the food placed in the refrigerator is not too much, there
may be the following two situations: i) the refrigerator very low, this means that the
control system is probably out of order; ii) the control system works normally, and there
are troubles in the refrigerating system or other parts.
1) Temperature is set improperly
a) The temperature control knob is set to the «coldest» position. This position is to be
used for fast freezing or continuous running, its temperature for power off is too low,
therefore, the compressor won›t stop and the temperature in the refrigerator becomes
lower and lower.
b) Inspection method: check the temperature control knob to see whether it is set in
the position «coldest».
2) Thermostat is malfunctioning and makes the compressor running continuously
Analysis of Trouble When the thermostat doesn›t work normally, it will make the
compressor run continuously, and hence very low temperature will be achieved in the
refrigerator. The fault is generally due to the fact that the contacts of the thermostat
cannot be released. Remedy Dismantle the thermostat and make a through checkup, if
it is totally out of functioning, replace it with a new one.
3) evaporation temperature is too high in refrigerating system, resulting in lower
refrigerating capacity and hence continuous running of compressor Analysis of Trouble
Leakage of refrigerant and clogging in a refrigerating system will directly affect its
refrigerating capacity. Due to the reduction in its refrigerating capacity, the refrigerator
temperature cannot reach its rated value, the thermostat won›t work, thus the
compressor runs continuously. When the evaporation temperature in the system is too
high, the temperature sensing agent in the temperature sensor is also hotter, therefore,
sensing agent from the temperature sensor. Remedy Remove the relay cover to check
up its contacts, if they are open, this means that the original setting is not properly set
or temperature sensing agent has leaked out of the temperature sensor. Try to turn the
adjusting stem of this value in the direction of the lower temperature graduation, then
check the contacts to see whether they are closed. If they are still not closed, dismantle
the temperature sensing disc and then immerse it into warm water to see whether
the contacts actuate, if not, it can be preliminarily determine that temperature sensing
agent has leaked out, and it must be replaced with a new thermostat.
4) Motor troubles and other electric faults
a) Motor windings have been burned or short-circuited between turns Analysis of
Trouble When motor windings have been burned or short-circuited between turns, the
fuse will be blown repeatedly, and the blowout occurs particularly at the instant when
you close the knife switch. Remedy Check the terminals and the outer casing to see
whether they are short-circuited, and measure the resistance of each phase with an
avometer. If short circuit occurs or the resistance of a certain phase is low, this means
that short circuit does exist in the windings and/or between turns, and insulation layers
have been burned or deteriorated. A megameter can be used in this inspection, too. I
f the insulation resistance is lower than 2 MW, this means that the insulation layer is
already breakdown. If the motor has been burned, repair it or replaced it with a new
one.
b) Fault of control relay Analysis of Trouble Overheat, burnout or wear of control relay
contacts may occur generally. All these will cause poor contact in electricity. Remedy
Dismantle it to repair, or replace it with a new one.
c) Poor electric contactor in thermostat Analysis of Trouble Burnout of contactor and
leakage of temperature sensing agent may occur generally. Remedy Replace the old
with a new one.
d) Check the terminals for loose connection and electric circuits for other abnormal
phenomena.
5) Mechanical faults of compressor
a) Seizing of shaft This phenomenon is caused mostly by poor lubrication, such ad
insufficient quantity of lubricant, clogging in the lubricant oil line, or intermittent
lubricant oil supply. Dirt and other impurities in the lubricant oil will increase its viscosity