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impurities in the lubricant oil will increase its viscosity 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, the
thermostat is unable to cut off the power supply to the compressor and stop it.
Remedy
If it has been found that the refrigerant in the system is insufficient in quantity, recharge it
with refrigerant. In case clogging occurs, disassemble the part where it is blocked. If the
evaporation temperature is too high, settle this problem with an appropriate quantity of
refrigerant.
4) No stoppage of compressor due to damaged heat-insulation layer inside case body
