SERVICE MANUAL
Model:HRF-660S
27
Issue 201001
Rev.
Ref1001S008V0
During the normal operation of compressor ,a slight and uniform hum sound due to undulation
of electric current can be heard generally ,this is a normal phenomenon .However ,if it sounds like
“tong ,tong …”,i.e., an impact sound inside the compressor ,this means that a large quantity of wet
vapor of refrigerant or refrigerating oil has come into the compressor cylinder; if it sounds like
“dang ,dang…”, a striking sound of metal parts inside the compressor ,this means that some moving
parts have loosened (note to differentiate this sound from those formed during starting or stopping the
compressor).
b) Listen to the sound caused by the flowing of gas in the evaporator
Open the refrigerator door while the compressor is in operation ,incline your ear and listen
attentively the gas flow sound inside the evaporator .If it sounds like gentle whistling accompanied by
a sound similar to water flowing ,this is the sound produced by the normal circulation of refrigerant
within the evaporator .In case only the gas flowing sound can be heard and there is no water flowing
sound ,this indicates that the refrigerant has already percolated .If neither the flowing sound nor the
gas sounds from the evaporator can be heard ,this means that the filter or capillary has been
clogged .
3) Touch and Feel
a) Feel the compressor when running, its temperature should be generally less than 90 in the
normal state (it may exceed 90 in case of running for a longer period of time).
b) After the compressor has operated normally for 5~10 minutes, touch and feel the
condenser ,the temperature of its upper part should be higher than that of its lower part (or its right
part is hotter than its left part ,depending on the type of condenser coil ),this indicates that the
refrigerant is circulating . If the condenser is not hot, this means the leakage of refrigerant .In case the
condenser radiates heat for only several minutes and then cools down, this means that the filter and
capillary have been clogged .As for the forced air cooling condenser, hot air will be blown out of it; this
means that the system is out of order.
c) Feel the filter’s temperature .During the normal operation of refrigerating system ,the
temperature on the filter’s surface should be a little higher than the ambient temperature ;if you touch
it with your hand ,you will have a sense of slight heat .In case dew condensation appears due to the f
Maintenance Service and Trouble Shooting ambient temperature ,this means that most meshes of its
screen has been clogged ,resulting in an obstructed flowing of refrigerant ,thus causing a drop in
temperature due to throttling .
d) Feel the temperature of exhaust gas from the refrigerating system .the exhaust gas should be
very hot and this is the normal working state .For those refrigerator with enclosed type of compressor
refrigerating system, no frost or dew drop will from on the gas suction tube, otherwise, there is
something wrong in the system (Frosting and dew condensation may appear for a very short time
period when just starting the machine, this is a normal phenomenon). Because a refrigerator is a
combination of several components ,they are related and have influence on each other .In case an
abnormal phenomenon has been found through the above-mentioned checkups ,you need not to
