Symptom Diagnosis; Pressure Test Chart (R-134A System) - Daewoo Nubira Owner's Manual

MANUAL CONTROL HEATING, VENTILATION, AND AIR CONDITIONING SYSTEM 7B – 17
TEST RESULTS
Discharge pressure After stopping the compres-
abnormally high sor, the pressure drops
about 299 kPa (28 psi)
quickly, then falls gradually.
The condenser is exces-
sively hot.
There is reduced or no air-
flow through the condenser.
The condenser or the radia-
tor fan is not working prop-
erly.
The line to the condenser is
excessively hot.
Discharge pressure The condenser is not hot.
abnormally low
The high and low pressures
are balanced soon after
stopping the compressor.
Low side pressure is higher
than normal.
Faulty compressor seal.
The outlet of the expansion
valve is not frosted, low
pressure gauge indicates
vacuum.
Moisture in the system.
Suction pressure ab- The condenser is not hot.
normally low
The expansion valve is not
frosted and the low pres-
sure line is not cold. Low
pressure gauge indicates a
vacuum.
Faulty expansion valve.
The discharge temperature
is low and the airflow from
the vents is restricted.
The expansion valve is
frosted.
The receiver/drier outlet is
cool and the inlet is warm.
DAEWOO V–121 BL4

SYMPTOM DIAGNOSIS

PRESSURE TEST CHART (R–134a SYSTEM)
RELATED SYMPTOMS PROBABLE CAUSE
There is air in the system.
There is excessive refrigerant in
the system.
The condenser or the radiator fins
are clogged.
S Check the voltage and the
fan rpm.
S Check the fan direction.
Restricted flow of refrigerant in
the system
Insufficient refrigerant in the sys-
tem.
Faulty compressor pressure relief
valve.
Faulty expansion valve.
Recover, evacuate, and recharge
the system.
Insufficient refrigerant in the sys-
tem.
Frozen expansion valve.
The evaporator is frozen.
The expansion valve is clogged.
The receiver/drier is clogged.
REMEDY
Recover, evacuate and re-
charge the system with the
specified amount of refrig-
erant.
Recover, evacuate and re-
charge the system with the
specified amount of refrig-
erant.
Clean the condenser or the
radiator fins.
Locate and repair the re-
striction.
S Check the system for a
leak.
S Charge the system.
Repair or replace the com-
pressor.
Replace the expansion
valve.
Repair the leaks. Recover,
evacuate, and recharge the
system.
Replace the expansion
valve.
Clear the restricted evapo-
rator case drain.
Clean or replace the expan-
sion valve.
Replace the receiver/drier.