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3) There Is Air Left In The Refrigerating System
Analysis of Problem
Residual air in the refrigerating system will reduce its refrigerating efficiency.
Major effects are an increase in temperature of the segment from the compressor
outlet to the condenser inlet and an increase in gas suction and exhaust pressures.
However, the gas exhaust pressure will not exceed its rated value. Due to the air in
the system, both the gas exhaust pressure and temperature will rise. In addition,
the sound of gas flowing will become intermittent and louder.
Remedy
Turn off the refrigerator, and wait for several minutes. Next, open and evacuate
the tubing. Then refill the system with refrigerant.
4)
Low efficiency of compressor
Analysis of Problem
Low efficiency of a refrigerating compressor refers to the actual reduction of gas
discharge capacity and the corresponding reduction of refrigerating capacity
under the condition that the refrigerant in the system is unchanged. This typically
occurs when the compressor has been is use for a long time.
Remedy
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. Inspect to see
if there is pressure at the discharge port with your finger. In a
normal compressor, it is difficult block the discharge port with
your finger.
5) Too thick frost layer formed on evaporator
Analysis of Problem
If a direct cooling refrigerator is to be used for a prolonged period, make sure
that you 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 fall to the prescribed range.
Remedy
Turn the refrigerator off and prepare for defrosting. Open the refrigerator’s
door to let air inside or use a fan to speed up air moving into the refrigerator to
quicken the defrosting process. Never strike the frost layer with any iron tools or
wooden stick in order not to damage the evaporator tubing
.
