821 / 1526
40
AIRCONDITIONING
6.
Excessive Refrigerant, or Insufficient
Condenser Cooling
Problem
Cause
Check and remedy
- Check refrigerant
quantity.
1. Pressure is high
- Slowly vent out re-
on both low pres- Excessive frigerant if over-
sure and high
refrigerant
charged.
pressure sides.
- Check and repair
2. Bubbles can not
Poor con-
condenser fan.
be seen in the
denser
- Check vehicle cool
sight glass
cooling
ing system.
7. Air Entered in the Cycle
Problem
Cause
Check and
remedy
1. Pressure is high
on both low pres-
sure and high
- Replace the refrig-
pressure sides.
erant
2. The low pressure Air is en-
- Be sure to evacu-
piping is hot to
tered in the ate the air after fin-
the touch.
cycle
ishing the remedy.
3. Bubbles are visi-
ble in the sight
glass
8. Expansion Valve Opens too Far
Problem
Cause
Check and
remedy
1. Pressure is high
- Check expansion
on both low pres-
valve.
sure and high
- Check the installa-
pressure sides.
tion condition of
2. Frost (dew) ap-
Expansion the temperature
pears on the low valve fault
sensing bulb.
pressure side pip-
- This problem fre-
ing
quently occurs af-
ter replacing the
expansion valve
Fig. 58 - Excessive refrigerant, or insufficient
condenser cooling
Fig. 59 - Air entered in the cycle
Fig. 60 - Expansion valve opens too far