Haier RF-8888-279, Service Manual

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Remedy
Replace the old one with a new one.
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: 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
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.
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