Magic Chef MCSF-5585BSS, Instruction Manual

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17
Three Essentials for Checkup
1) Look
a) Check the tubing of refrigerating system for cracks and various welding points for
leaks ;if leakage occurs ,an oil stain can be seen definitely .
b) Check the suction and exhaust pressure values (high pressure and low pressure) of
compressor to see whether they are normal .
c) Check the conditions of frost attached to its evaporator and gas return tube .It is
abnormal if frost has formed on part of the evaporator orthere is no frost attached to it .
d) Pay attention to the speed of temperature drop inside freezer compartment .It is
abnormal if the speed of temperature drop is obviously slower than the corresponding
normal speed .
e) Check the environment to see whether it is suitable for placing a refrigerator .
f)Check refrigerator door seal, case ,table surface and heat insulation layer .
g) Look at the main control board to ascertain if various indication states are normal.
2) Listen
a) Listen to the noises produced when the compressor is runningHums from a fully
enclosed aggregate unit is the sound caused by overload indicating that the motor
cannot be started normally ,meanwhile ,a clattering sound can be heard from inside the
start relay ,which is producedbecause the start contacts cannot be released normally
.A whistling sound is caused by the high pressure gas flowing out of the crack of the
pressuretube inside the compressor ,and clucks are the sound of striking after the
suspended spring inside the compressor has broken . 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
¼»,i.e., an impact sound inside the compressor ,this means that a large quantity of wet
vapour of refrigerant or refrigerating oil has come into the compressor cylinder ;if it
sounds like «dang ,dang¼», 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).
4).For the direct cooling refrigerator ,a kind of irregular crack sound can be often heard
when the compressor is running for a certain period of time or has just stopped its
running .This sound is caused by the stress relief due to expansion and contraction when
temperature changes ,and will not affect the normal application of refrigerator .
6 Common Troubles in Refrigerators and Their Remedies
Causes for troubles occurring in refrigerators are closely related to the quality of
components and workmanship in assembling by manufacturers
as whether refrigerators are properly used and maintained .The parameters generally
used to express the working conditions of a refrigerator include
the temperature inside the refrigerator ,operation rate ,electric power consumption
,noise level ,and other functional indexes .If any one of these parameters is beyond its
permissible range ,this indicates that there is a fault or trouble in the refrigerator . During
the whole service life of a refrigerator ,the probability of troubles occurring within a
union time is called its failure rate .Making a comparison between the control circuit
system of a refrigerator and its refrigerating system ,we can find that the failure rate
of the former is higher ,and that of the thermostat is the highest . In troubleshooting
,the first thing you must do is to determine where the trouble comes from --- the
control system or the refrigerating system .There is general no trouble indicating
instrument mountedon the dome stic refrigerator ,locations and natures of troubles
should be determined according to their respective features ,therefore ,experience in
servicing is very important to troubleshooting. Service technicians with rich experience
can correctly locate them and take reasonable remedy measures based on their
comprehensive analysis of trouble characteristics as well asoperating conditions for
various kinds of refrigerators .