Honda Civic Service Manual page 1452

A/C System Service
Pressure Test Chart
NOTE: Performance Test is on page 22-24,
Test results
Related symptoms Probabl€ cause Remedy
D i s c h a r g e ( h i g h )
pressure aDnor-
m a l l y h i g h
After stopping compressor. pres-
sure drops to about 200 kPa
{2.0 kgflcm,,28 psi) quickly, and
then falls gradually.
Air in system Recover, evacuate, and
recharge with specified amount.
Evacuation: see page 22-45
Charging: see page 22-46
Reduced or no air flow through
condenser
. Clogged condenser fins
. Condenser fan not work-
ing properly
Clean.
Check voltage and fan rpm.
Check fan direction.
Line to condenser is excessively
hot.
Restricted flow of refriger-
ant in system
Restricted lines
Discharge pres-
sure abnormally
High and low pressures are bal-
anced soon after stopping compres-
sor, Low side is higher than normal.
. Faulty compressor dis-
charge valve
. Faulty compressor seal
Replace the compressor.
Outlet of expansion valve is not
frosted, low pressure gauge indi-
cales vacuum.
. Faulty expansion valve
. Moisture in system
. Replace,
. Recover, evacuate, and
recharge with specified
amount.
Suction (low)
pressure abnor-
mally low
Expansion valve is not frosted, and
low oressure line is not cold. Low
pressure gauge indicates vacuum.
. Frozen expansion valve
. Faulty expansion valve
ReDlace the exoansion valve.
Discharge temperature is low. and
the air flow from vents is restricted.
Frozen evaporator
Run the fan with compressor
off. then check A,/C thermostat.
Exoansion valve is frosted. Clogged expansion valve
Clean or replace.
Receiver/dryer outlet is cool, and
inlet is warm (should be warm
during operation).
Clogged receiver/dryer Replace.
Suction pres-
sure abnormally
h i g h
Low pressure hose and check
joint are cooler than the tempera-
ture around evaporator.
. Expansion valve open too
long
. Loose expansion capillary
tube
Repair or replace.
Suction oressure is lowered when
condenser is cooled bv water.
Excessive refrigerant in sys-
tem
Recover. evacuate, and
recharge with specified amount.
High and low pressure are equal-
ized as soon as the compressor is
stopped, and both gauges fluctu-
ate while running.
Faulty gasket
Faulty high pressure valve
Foreign particle stuck in
high pressure valve
Replace the compressor.
Suction and dis-
charge pres-
sures abnormally
h i g h
Reduced air flow through con-
denser.
. Clogged condenser fins
. Condenser fan not work-
ing properly
Clean condenser.
Check voltage and fan rpm.
Check fan direction.
Suction and dis-
charge pressure
a b n o r m a l l y l o w
Low pressure hose and metal end
areas are cooler than evaporator.
Clogged or kinked low pres-
sure hose parts
Repair or replace.
Temperature around expansion
valve is too low compared with
that around receiver/dryer.
Clogged high pressure line Repair or replace.
Refrigerant leaks
Compressor clutch is diny, Compressor shaft seal leaking Replace the compressor.
Compressor bolt{s) are diny. Leaking around bolt(s)
Tighten bolt(s) or replace com-
pressor.
Compressor gasket is wet with oil. Gasket leaking Replace the compressor.
22-26