Haier BC-117A Series, Руководство по обслуживанию

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make a note of from where it leaks ---welding points and parts .After having
them repaired ,recharge refrigerant .
There are so many joints and sealed surfaces in a
refrigerator ,accordingly ,quite a lot potential leak points do exist in the
system .In troubleshooting ,pay attention to those parts that are liable to
leak ,check main connection points for oil seepage and tubing for cracks .If
there is no severer leak point ,charge the system with nitrogen and detect
leak
points with the commonly adopted method ,repair
them ,evacuate ,charge the system with refrigerant ,and then turn on the
refrigerator to make a test run .
2) Too much refrigerant charged into the system
Analysis of Trouble
a) In case the amount of refrigerant charged into the system exceeds its
nominal capacity ,the superfluous refrigerant will of course take some space
of the evaporator ,thus reducing its heat-dissipation area and hence the
refrigerating efficiency of the system .The abnormal phenomena caused by
this reason are as follows :the gas suction and exhaust pressures are
generally higher than their respective normal values ,the temperature of its
condenser is higher and the electric current of the compressor rises ,loose
frost forms on the evaporator ,the refrigerator temperature drops slowly ,and
frost appears on the gas return tube .
b) In case excessive refrigerant has been charged ,the liquid refrigerant
that cannot evaporates in the evaporator will return to the compressor ,and
thus a phenomenon of
“
liquid striking
”
will occur .The liquid refrigerant
evaporates and effervesces as soon as it flows into the refrigerating oil at the
bottom of compressor .If the condition is severe ,foams will fill all over inside
the compressor housing and be sucked by the piston ,causing damage to the
components of compressor .
Remedy
According to the operating procedures ,it is mandatory to turn the machine
off ,and several minutes later ,open the refrigerant charging tube and let the
refrigerant escape from it ,replace the dry filter ,recharge refrigerant after
evacuating ,and then seal the charging port .
3) There is air left in the refrigerating system
Analysis of Trouble
Residual air in the refrigerating system will reduce its refrigerating
efficiency .The prominent phenomena are the increase in its gas suction and
exhaust pressures (however ,the gas exhaust pressure will not exceed its
rated value ),obvious increase in temperature in the segment from the
compressor outlet to the condenser inlet .Because there is air in the
system ,both the gas exhaust pressure and temperature will rise ,and
moreover ,the gas flowing sound is intermittent and obviously louder .
Maintenance Service and Trouble Shooting