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Maintenance Service and Trouble Shooting
6 Common Troubles in Freezers and Their Remedies
Causes for troubles occurring in Freezers are closely related to the
quality of components and workmanship in assembling by manufacturers
as whether Freezers are properly used and maintained .The parameters
generally used to express the working conditions of a Freezer include
the temperature inside the Freezer ,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 Freezer .
During the whole service life of a Freezer , the probability of troubles
occurring within a union time is called its failure rate .Making a comparison
between the control circuit system of a Freezer 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
mounted on the dome stic Freezer ,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 as operating
conditions for various kinds of Freezers .
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 or
there 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
Freezer .
f)
layer .
Check Freezer door seal ,case ,table surface and heat insulation
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 running
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