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FATC
34
2
Excessive refrigerant
or insufficient conden-
ser cooling.
Condition
•
Air conditioner does not cool effectively
Symptoms in refrigerant cycle
•
Pressure on both the high and low
pressure sides is high.
Cause
•
Refrigerant is overcharge in the refrig-
erating cycle causing poor cooling
performance
•
Condenser cooling performance is
poor.
•
Fluid coupling on fan is slipping.
Diagnosis
•
Excessive refrigerant in the refrigerating
cycle.
•
Overcharged refrigerant.
•
Poor condenser cooling performance.
•
Condenser fins blocked or fan belt
loose.
•
Slipping radiator fan fluid coupling.
•
Silicone oil leaking from the coupling.
Countermeasures
•
Clean the condenser.
•
Tighten the fan belt to the
correct tension.
•
Repair the fluid coupling
and adjust silicone oil
quantity to the proper level.
•
Above are all normal check
the refrigerant.
3
Entry of moisture in
the refrigerant cycle
Condition
•
Air conditioner alternately cools and
does not cool.
Symptoms in refrigerant cycle
•
During operation, the pressure on the
low pressure side alternates between
vacuum and normal.
Cause
•
The moisture mixed in the refrigerant in
the refrigerating cycle freezes in the ex-
pansion valve orifice, blocking the
cycle. After a time, the ice melts and
normal conditions return
Diagnosis
•
The drier is in an oversaturated condi-
tion.
•
The moisture in the refrigerating cycle
freezes the expansion valve orifice, im-
peding refrigerant circulation.
Countermeasures
•
Remove the moisture by
repeated evacuation.
•
Recharge new refrigerant
to the specified amount.