Technical Tips

Technical Tip #1

Chrysler with a mechanical thermostatic compressor clutch cycling switch, with the thermostatic switch capillary tube inserted in the refrigerant line.  This system may experience a problem with the clutch cycling to quickly.  To correct the problem, pull about 1 to 1 1/2 inches of the thermostatic switch's capillary tube out of the tube extending into the refrigerant line.  Then check for proper clutch cycling, system pressures and duct temperature.

Technical Tip #2

1985-1993 Cadillac Computer prevents compressor clutch from engaging and displays code 46 or 4.  These codes result from low temperature at the evaporator inlet, rapid cycling or restricted orifice tube.  If the system is operating properly and the codes continue, replace the low temperature sensor with an original equipment type.  DO NOT try to change to a R134a sensor, replace with a R12 original equipment type only.  Replacing the low temperature sensor usually corrects the problem.  If the codes continue and the system is functioning properly, add 2 oz of R134a refrigerant.  Then test the system for correct pressures and duct temperature.

Technical Tip #3

Chrysler K-cars; when retrofitting Chrysler Corp. K-cars which use a 2 blade cooling fan, the 2 blade fan needs to be changed.  The 2 blade fan does not pull enough air across the condenser.  Replace with a fan with more blades which will pull more air across the condenser.

Technical Tip #4

Click below to view R12 and R134a TPRC - (Acrobat Reader file) : 

Temperature Pressure Relationship Chart