26
megameter. If the insulation resistance is lower than 2 M
Ω
, this means that the
insulation layer has a breakdown already. If the motor is damaged, repair or replaced
it with a new one.
ii) Control relay is faulty
Analysis of Trouble
Overheating, burns or wearing of control relay contacts will generally occur if this is
true. All these will cause poor contact in electricity.
Remedy
Dismantle it for repairs, or replace it with a new one.
iii) Poor electric contractor in thermostat
Analysis of Trouble
Damaged contractor and leakage of temperature sensing agent will generally occur if
this is true.
Remedy
Replace the old one with a new one.
iv) Check the terminals for loose connection and electric circuits for other
abnormal phenomena.
e) Mechanical faults of compressor
i) Seizure of shaft
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:
