This is normally caused by poor lubrication, insufficient quantity of lubricant, clogging in the lubricant oil’s line, or intermittent lubricant oil supply. Dirt and other impurities in the lubricant will increase its viscosity and cause the shaft to be seized. Copper plating may also result in the seizure of the shaft.
ii)Seizing of piston
This happens because the fit clearance between the piston and cylinder is too small or expansion due to heat.
iii)How do you know that the shaft and piston have been seized
When the refrigerator is switched on, the compressor will not start running. A slight hum sound will be heard and several seconds later, the thermal protective relay will actuate and open the contacts. This process will occur repeatedly, but the compressor will not start.
Compressor will not 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)Control system is probably out of order
ii)The control system works normally but there are problems in the refrigerating system or other parts
a)Temperature is set improperly
i)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 will not stop and the temperature in the refrigerator becomes lower and lower.
ii)Inspection method: check the temperature control knob to see whether it is set in the position “coldest”.
b)Thermostat is malfunctioning and makes the compressor running continuously
Analysis of Trouble
When the thermostat does not work normally, it will make the compressor run continuously, and hence very low temperature will be achieved in the refrigerator. The fault is generally because 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 with a new one.
c)Evaporation temperature is too high in refrigerating system, resulting in lower refrigerating capacity and hence continuous running of compressor
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