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 
A thermostat generally controls start and stop of the compressor. 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, find 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 supplies, 
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. 
-34-