Magic Chef MCSF-5585BSS, Instruction Manual

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recharge the system with refrigerant .
4) Low efficiency of compressor
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 refrigerator 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 refrigerator cannot drop down to the prescribed range . Remedy
Turn the refrigerator off ,and make preparations for defrosting ,open the refrigerator
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
severer leak point ,charge the system with nitrogen and detect leak points with the
commonly adopted method ,repair them ,evacuate ,charge the system with refrigerant
,and then turn on the refrigerator to make a test run .
2) Too much refrigerant charged into the system
Analysis of Trouble
a) In case the amount of refrigerant charged into the system exceeds its nominal
capacity ,the superfluous refrigerant will of course take some space of the evaporator
,thus reducing its heat-dissipation area and hencethe refrigerating efficiency of the
system .The abnormal phenomena caused by this reason are as follows :the gas suction
and exhaust pressures are generally higher than their respective normal values ,the
temperature of its condenser is higher and the electric current of the compressor rises
,loose frost forms on the evaporator ,the refrigerator temperature drops slowly ,and
frost appears on the gas return tube .
b) In case excessive refrigerant has been charged ,the liquid refrigerant that cannot
evaporates in the evaporator will return to the compressor ,and thus a phenomenon
of «liquid striking» will occur .The liquid refrigerant evaporates and effervesces as
soon as it flows into the refrigerating oil at the bottom of compressor .If the condition
is severe ,foams will fill all over inside the compressor housing and be sucked by the
piston ,causing damage to the components of compressor . Remedy According to the
operating procedures ,it is mandatory to turn the machine off ,and several minutes later
,open the refrigerant charging tube and et the refrigerant escape from it ,replace the dry
filter ,recharge refrigerant after evacuating ,and then seal the charging port .
3) There is air left in the refrigerating system
Analysis of Trouble Residual air in the refrigerating system will reduce its refrigerating
efficiency .The prominent phenomena are the increase in its gas suction and exhaust
pressures (however ,the gas exhaust pressure will not exceed its rated value ),obvious
increase in temperature in the segment from the compressor outlet to the condenser
inlet .Because there is air in the system ,both the gas exhaust pressure and temperature
will rise ,and moreover ,the gas flowing sound is intermittent and obviously louder .
Remedy After shut down for several minutes ,open the tubing ,evacuate it and then