REFRIGERATION SYSTEM Checking of Refrigerant Charge 1. RUN ENGINE AT FAST IDLE 2. OPERATE AIR CONDITIONER AT MAXIMUM COOLING FOR A FEW MINUTES 3. CHECK AMOUNT OF REFRIGERANT Observe the sight glass on the receiver. Item | Symptom | Amount of refrigerant | Remedy 1 | Bubbles present in sight glass | Insufficient | Check for leak with gas leak tester 2 | No bubbles present in sight glass | None, sufficient or too much | Refer to items 3 and 4 3 | No temperature difference between compressor inlet and outlet | System is empty or nearly empty | Evacuate and charge system. Then check for leak with gas leak tester 4 | Temperature between compressor inlet and outlet is noticeably different | Proper or too much | Refer to items 5 and 6 5 | Immediately after the air conditioner is turned off, refrigerant in sight glass stays clear | Too much | Discharge the excess refrigerant to specified amount 6 | When the air conditioner is turned off, refrigerant foams and then stays clear | Proper | Installation of Manifold Gauge Set NOTE: Fittings for attaching the manifold gauge set are located on the compressor service valves. 1. CLOSE BOTH HAND VALVES OF MANIFOLD GAUGE SET 2. INSTALL CHARGING HOSES OF GAUGE SET TO SERVICE VALVES Connect the low pressure hose to the suction service valve and the high pressure hose to the discharge service valve. Tighten the hose nuts by hand. NOTE: Do not apply compressor oil to the seat of the connection.