Haier BC-117A Series, Service Manual

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compressor can be started easily (if there is no damage to the compressor
parts) and its operating current becomes low ,its gas suction pressure is high
and discharge pressure is lower ,the gas discharge tube feels rather cold ,no
sound of gas eruption from the liquid in the evaporator can be heard ,and no
will gush out of the process tube if you cut it open after shutdown .
Remedy
Check the whole machine , particularly those locations which are liable to
leak .After leak points have been found ,repair them or replace them with new
parts according to specific circumstances ,then evacuate the system and
finally charge refrigerant.
2) Refrigerating system has been clogged
a) Clogged with Ice
Analysis of Trouble
The dryness treatment for the major parts in the refrigerating system has
been performed improperly, the effect of air purging for the whole system is
not good ,or the water content in the refrigerant is out of standard ,all these
will cause the expansion valve to be clogged with ice .The symptom for this
trouble are as follows :the refrigerator sometimes can refrigerate and
sometimes cannot :the refrigerator compartment works normally at the
beginning ,but after working for a certain period of time ,frosting begins at the
clogged position ,evaporation temperature reaches below 0
℃
, water will
accumulate at the narrow part of the capillary and clog it gradually ,then frost
begins to melt at the evaporator ,no gas flowing sound can be heard ,and the
gas suction pressure assumes a state of vacuum .Note that these
phenomena will appear intermittently ; sometimes ,the refrigerator works
well ,and sometimes not well .In order to determine whether it is clogged with
ice ,heat the suspicious points with hot water to make ice melt ,and after a
while if a gas flowing sound resulting from an abrupt gush is heard and the
gas suction pressure rises as well ,it can be confirmed that the trouble is
caused by ice clogging .
Remedy
If there is too much moisture in the refrigerating system, it is advisable to
release the refrigerant, purge the tubing with nitrogen, and then charge the
system with the filtered refrigerant. However, the commonly adopted method
is to connect a filter with moisture absorbers (such as silica-gel, anhydrous
calcium chloride) to the refrigerating system so as to filter out the moisture
from the system, then replace the filter, evacuate it again and finally charge
the system with refrigerant.
b) Clogged with dirt in capillary
Analysis of Trouble
The capillary inlet is a place where coarse-grained dirt or refrigerant oil in
the system will tend to settle down and clog it. In case considerable dirt
Maintenance Service and Trouble Shooting