Supplying Climate Control Systems to the Vehicle Market for Over Half a Century.

Refrigerant and Service Recommendations


  • All existing R-12 systems should be serviced with R-12 only, as long as R-12 is available. The E.P.A. states that adequate quantities of R-12 for service will be available for several years.
  • All existing R-134a systems should be services with R-134a only. R-134a is readily available, and reasonably priced.
  • At this time, no "Drop-in" replacements for R-12 exist. Various refrigerant blends are being marketed for use in R-12 systems. Use of any blend requires system modifications for proper functional and legal use. None of these blends have been tested and approved by Evans Tempcon.
  • If R-12 is absolutely not available to service a system, a retrofit to R-134a will be necessary. R-134a is the only refrigerant approved by the major automotive manufacturers and the E.P.A. for retrofit.
  • R-134a is the only retrofit refrigerant approved by Evans Tempcon at this time. Use of any other retrofit refrigerant can result in poor system performance, system damage, and dangerous operation.

If an R-12 system is to be retrofitted to use R-134a, the following new components must be installed:

  • R-134a compatible Compressor and Oil
  • R-134a compatible Receiver-Drier.
  • R-134a compatible Thermostatic Expansion Valve.
  • R-134a compatible O-rings at all fitting connections.
  • R-134a compatible Barrier-type Hose Assemblies.
  • R-134a compatible Pressure Switches and Switch Settings.
  • Evaporators and Condensers must be flushed with flushing solvent to remove R-12 mineral oil.

Contact Evans Tempcon for specific recommendations that may apply to your make, year, and model vehicle equipped with an Evans System.


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