Haier RF-8888-279, Service Manual

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17
During the entire service life of a refrigerator, the probability of problems occurring within a
specific time is called its failure rate. A comparison between the control circuit system of a
refrigerator and its refrigerating system indicates that the failure rate of the former is
higher. When troubleshooting, the first thing you must do is to determine whether the
source of the problem is the control system or the refrigerating system.
There is usually no troubleshooting instrument for the domestic refrigerator. The location
and nature of problems must therefore be determined according to their respective
features. Experience in servicing is very important for troubleshooting. Well-experienced
service technicians can correctly identify and solve problems based on their comprehensive
analysis of the characteristics of the particular problems as well as the operating conditions
for various kinds of refrigerators.
Three Essential Things To Note During A Checkup
Look
Check the tubing of the refrigerating system for cracks and various welding points for
leakages. If there is a leakage, a distinct oil stain will be seen.
Check the suction and the exhaust pressure valves (high pressure and low pressure) of
compressor to see whether they are normal.
Check the conditions of the frost attached to its evaporator and gas return tube. It is
abnormal if frost has formed on part of the evaporator or there is no frost attached to it.
Pay attention to the rate at which the temperature decreases in both the refrigerator and
freezer compartments.
Check the environment to see whether it is suitable for the refrigerator.
Check refrigerator door seal, case, table surface, and heat insulation layer.
Look at the main control board to ascertain if various indication states are normal.
Listen
Listen to the noises made while the compressor is running. During the normal operation of
compressor, a slight and uniform humming sound due to undulation of electric currents will
be heard. The sounds listed below indicate a malfunction.
Humming sounds from a fully enclosed aggregate unit indicate that the motor was not
started properly.
Clattering sounds from the start relay indicate that the start contacts cannot be released
normally.
Whistling sounds indicate the release of high-pressure gas from a crack in the pressure tube
inside the compressor.
Clucking sounds indicate that the suspended spring inside the compressor has broken