Midea HS-36I, Service Manual

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Maintenance Service and Trouble Shooting
Analysis of Trouble
Low efficiency of a refrigerating compressor refers to the actual
reduction of gas discharge capacity ,and hence the corresponding
reduction of refrigerating capacity ,under the condition that the refrigerant in
the system is unchanged .This phenomenon occurs mostly when the
compressor has been used for quite a long time ,its moving parts have
worn to a considerable degree ,fit clearance between various parts have
increased and sealing property of its gas valve has deteriorated ,resulting
in an decrease in its actual gas discharge capacity .
Methods of Judgment
Measure the high and low pressures with pressure gauges to see
whether they are normal .If an abnormal sound comes from the compressor
or the temperature of its causing is too high ,Cut the discharge port open
and operate the compressor ,feel it if there is pressure at the discharge port
with your finger (For a normal compressor ,its discharge port is difficult to
be blocked with your finger if you just apply a little effort).
5) Too thick frost layer formed on evaporator
Analysis of Trouble
If a direct cooling appliance is to be used for a prolonged period of
time ,be sure to defrost its evaporator regularly ;if you fail to do so ,the frost
layer on the evaporator tubing will become thicker and thicker .Heat
conduction will be severely affected when the whole tubing is wrapped with
a transparent ice layer ,and finally the temperature in the appliance
cannot drop down to the prescribed range .
Remedy
Turn the appliance off , and make preparations for defrosting ,open the
appliance door to let the air come in ,or use a fan to speed up air flowing
so as to shorten the time needed for defrosting .Never strike the frost layer
with any iron tools or wood stick in order to avoid damage to the evaporator
tubing .
6) Refrigerating oil left in evaporator tubing
Analysis of Trouble
During the process of refrigerating cycles , a little refrigerating oil may
remain in the evaporator tubing ,and after a longer time of operation ,if
there is considerable refrigerating oil left in the evaporator ,the heat
conduction effect will be severely affected ,thus causing a poor refrigerating
effect .
Remedy
It is quite difficult to determine whether this trouble is caused by the
refrigerating oil left in the evaporator tubing ,because this kind of
phenomenon and other several trouble are tends to be confused .Generally
speaking ,you can make a judgment based on the frost formed on the
evaporator .If the frost does not cover the evaporator , and moreover ,it is
loosely formed ,you can make a judgment that the deterioration of
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