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Refrigerant: Testing and Inspection





HEATING / AIR CONDITIONING: REFRIGERANT: ON-VEHICLE INSPECTION

1. INSPECT REFRIGERANT VOLUME

(a) Check the sight glass on the liquid tube sub-assembly.





(1) Prepare the vehicle according to the chart below.





(2) Compare the sight glass to the following chart.





*: Bubbles in the sight glass with the vehicle's interior temperature above 35°C (95°F) can be considered normal if cooling is sufficient.

2. INSPECT REFRIGERANT PRESSURE WITH MANIFOLD GAUGE SET

HINT
This is a method where a manifold gauge set is used to help locate the problem.

(a) Read the manifold gauge pressure when the following conditions are met:

Test conditions:

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

* The engine is running at 1500 rpm.

* The blower speed control switch position is at "HI".

* The temperature control dial position is at "COOL".

* The A/C switch is on.

* Doors are fully open.

* The engine switch is in a position that enables the A/C compressor to run.

(1) Normally functioning refrigeration system





Gauge Reading





(2) Moisture is present in the refrigeration system.









(3) Insufficient cooling









(4) Poor circulation of refrigerant









(5) Refrigerant does not circulate.









(6) Refrigerant is overcharged or cooling effectiveness of condenser is insufficient.









(7) Air is present in the refrigeration system.









(8) Expansion valve malfunction









Insufficient compressor compression









Gauge readings (Reference)