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Insufficient Cooling

  1. Check that fan motor operates at all 4 speeds, air duct closes off outside air intake and heater water valve is closed. Adjust compressor belt tension and clean condenser.
    NOTE: If system doors allow air leaks, evaporator will freeze up and testing will not be possible.
  2. Adjust engine speed to 2500 RPM. Position controls for maximum cooling and high blower. Insert thermometer in left register and close all other ducts. With vehicle out of sun, close all windows and doors. Connect pressure gauges and check readings.
  3. If both gauges read too high, replace expansion valve. If both read too low, recharge system after locating leak. If both readings are normal, go to step 4). If pressure side is too high and suction side is normal, go to step 5). If pressure side is too low and suction side is too high, go to step 6). If pressure side is normal and suction side is too low, go to step 7).
  4. Turn compressor off and watch gauges. If readings equalize in 30 seconds, replace compressor. If readings take longer to equalize, check that capillary installation in evaporator is 7" (178 mm) long on all models.
  5. If installation is correct, run system at maximum cooling for 15 minutes. If thermometer indicates temperature is below 36°F (2°C) when compressor is turned off, or temperature is above 48°F (9°C) with compressor on, replace temperature switch.
  6. Check condenser fins and clean or straighten. If operation is still not correct, discharge system using approved refrigerant recovery/recycling equipment, until bubbles show in sight glass. Recharge until bubbles disappear and recheck pressures. If still incorrect, locate leaks and tighten fittings. Discharge system using approved refrigerant recovery/recycling equipment. Evacuate to remove all air and recharge system.
  7. Check for bubbles at sight glass. If present, repair leaks and recharge system. If no bubbles, check condenser-to-expansion valve line for kinks and repair if necessary. Feel along line from condenser-to-expansion valve. If there are no cold spots, replace expansion valve.
  8. If cold spot is felt, remove and flush out lines and condenser. Check for bubbles at sight glass. If there are no bubbles present, replace compressor. If bubbles are present, check for leaks. Repair and recharge system.
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