940 / 1002
HVAC
30
STEP INSPECTION
ACTION
or elsewhere
Are refrigerant’s high-pressure and
low-pressure values low?
No
Go to step 14
7
Verify whether malfunction is in
expansion valve and receiver /drier
or elsewhere immediately after A/C
compressor operates, does refrig-
erant’s
high-pressure
value
momentarily rise to correct value,
then fall and stay below it? (Is there
negative pressure on low-pressure
side?)
Yes
Go to next step
No
Go to step 10.
8
Verify whether malfunction is in
expansion valve or receiver/drier.
Turn A/C switch off and air condi-
tioner stop for 10 minutes start
engine turn both A/C switch and
fan switch on. Does malfunction
occur after compressor turn on?
Yes
Go to next step
No
Replace condenser and vacuum refrigerant line
more than 30 minutes by vacuum pump, and re-
frigerant to specified level.
(Since water has
intermixed in receiver/drier and it is saturated,
replacement is necessary.)
9
Verify that expansion vale heat-
sensing tube within cooling unit is
positioned securely and correctly is
expansion valve heat-sensing tube
within cooling unit securely in-
stalled in proper position?
Yes
Replace expansion valve.
(Since valve closes too
much replacement is necessary.)
No
Install heat-sensing tube securely in proper posi-
tion.
10
Inspect refrigerant lines inspect
refrigerant lines
Is piping free of damage and
cracks?
Are piping connections free of
oil grime? (visual inspection)
Are piping installation points on
a/c compressor free of gas
leakage?
Are piping installation on cooling
unit free of gas leakage?
Perform gas leak inspection us-
ing gas leak tester.
Are above items okay?
Yes
Go to next step
No
If piping or an A/C component is damaged or
cracked, replace it.
11
Inspect evaporator piping connec-
tions in cooling unit for gas leakage
are piping connections for evapora-
tor in cooling unit free of gas
leakage?
Yes
If the vane makes a noise, add 10ml of compres-
sor oil to the A/C compressor. Verify that the
noise is no longer heard. Adjust refrigerant to
specified amounts.
No
If piping is damaged or cracked, replace it.