Refrigerant

HEATING / AIR CONDITIONING: REFRIGERANT: ON-VEHICLE INSPECTION

1. INSPECT REFRIGERANT VOLUME

(a) Check the sight glass on the air conditioning tube assembly.





Text in Illustration





Test conditions:

Temperature at the air inlet is 30 to 35°C (86 to 95°F).

Engine is running at 1500 rpm.

Blower speed control switch is at HI.

A/C switch is on.

Temperature control switch is at the MAX. COOL position.

Doors are fully open.





HINT
*: If the ambient temperature is higher than usual but cooling is sufficient, bubbles in the sight glass are permissible.

2. INSPECT REFRIGERANT PRESSURE WITH MANIFOLD GAUGE SET

(a) This method uses a manifold gauge set to locate problem areas. Read the manifold gauge pressure when these conditions are established.

Test conditions:

Temperature at the air inlet with the switch set at RECIRC is 30 to 35°C (86 to 95°F).

Engine is running at 1500 rpm.

All doors are fully open.

Blower speed control switch is at HI.

A/C switch is on.

Gauge readings (Reference):





(1) Normally functioning refrigeration system.





Gauge Reading:





(2) The A/C system periodically changes between normal and improper function due to moisture in the refrigerant system.









(3) The A/C system does not function effectively due to insufficient refrigerant.









(4) The A/C system does not function effectively due to poor circulation of the refrigerant.









(5) The A/C system does not function or functions intermittently because the refrigerant does not circulate.









(6) The A/C system does not function effectively due to overcharged refrigerant or insufficient cooling of the condenser.









(7) The A/C system does not function due to air in the refrigeration system.

CAUTION:
The low-pressure piping may be very hot and cause serious burns.









(8) The A/C system does not function effectively due to an expansion valve malfunction.









(9) The A/C system does not function due to a defective compressor.