NANO

864 HVAC A/C SYSTEMPERFORMANCE TEST 1. Place the vehicle in a ventilated, shaded area free from excessive draught, with the doors and windows open. 2. Check that the surface of the condenser is not restricted with dirt, leaves, flies, etc. Clean as necessary. 3. Switch on the ignition and the air conditioner air flow control. Check that the blower is operating efficiently at low, medium and high speeds. 4. Switch off the blower and the ignition. 5. Check that the evaporator condensate drain tubes are open and clear. 6. Check the tension of the compressor driving belt, and adjust if necessary. 7. Inspect all connections for the presence of refrigerant oil. If oil is evident, check for leaks, and repair as necessary. NOTE: The compressor oil is soluble in refrigerant R134a and is deposited when the refrigerant evaporates from a leak. 8. Start the engine. 9. Set the temperature controls to max. cold and switch the air conditioner blower control on and off several times, checking that the magnetic clutch on the compressor engages and releases each time. 10.With the temperature control at maximum cooling and the blower control at high speed, warm up the engine and fast idle at rated rpm. 11. Gradually increase the engine speed to the high range and check the sight glass at intervals. 12.Check for frosting on the service valves. 13.Check the high pressure hoses and connections by hand for varying temperature. Low temperature indicates a restriction or blockage at that point. 14.Switch off the air conditioning blower and stop the engine. 15. If the air conditioning equipment is still not satisfactory, carry out a pressure test as previously described in this section. LEAK TEST SYSTEM The following instructions refer to an electronic type Refrigerant Leak Detector for use with R134a, which is the safest and most sensitive. 1. Place the vehicle in a well ventilated area but free from draughts, as leakage from the system could be dissipated without detection. 2. Follow the instructions issued by the manufacturer of the particular leak detector being used. 3. Commence searching for leaks by passing the detector probe around all joints and components, refrigerant gas is heavier than air. 4. Insert the probe into an air outlet of the evaporator or into the evaporator drain tube. Switch the air conditioning blower on and off at intervals of ten seconds. Any leaking refrigerant will be gathered in by the blower and detected. 5. Insert the probe between the magnetic clutch and compressor to check the shaft seal for leaks. 6. Check all service valve connections. 7. Check the condenser for leaks at the pipe unions. 8. If any leaks are found, the system must be discharged before rectification. 9. Rectify any leaks and recheck for leaks during evacuation prior to charging.