Choosing and Using a Retrofit Refrigerant for a CFC-12 Motor Vehicle Air Conditioner (MVAC)


CFC-12 (also known by the trade name Freon or Freon-12) is an ozone-depleting refrigerant and potent greenhouse gas that was widely used in air conditioners for automobiles and trucks for over 30 years, up until the mid-1990s. While use of CFC-12 in new vehicles has been banned since 1994, some vehicles built before then may still use it if they have not already been retrofitted to a non-ozone depleting refrigerant and they are still on the road. This page provides information for technicians preparing to retrofit a CFC-12 vehicles as well as those car owners who have a car originally manufactured with and continuing to use CFC-12 as the refrigerant, and who are considering a retrofit to a non-ozone depleting refrigerant.

Refrigerant Options & the SNAP Program

EPA’s Significant New Alternatives Policy (SNAP) program ensures the smooth transition to alternatives that pose lower overall risk to human health and the environment. The SNAP program reviews and approves or prohibits the use of alternative refrigerants.

For MVAC systems, when a substitute is approved, it is listed under SNAP as acceptable, subject to use conditions, for use in MVAC systems in new vehicles, to retrofit MVAC systems in existing vehicles, or for use in both. Note that some refrigerants are approved for use in new vehicles only and cannot be used as retrofits, and vice versa. HFC-134a and a variety of HCFC and HFC blend refrigerants, can be used to retrofit an MVAC system using CFC-12.

Use Conditions for Retrofits

SNAP has found HFC-134a and several HCFC and HFC blend refrigerants acceptable, subject to use conditions, for use as retrofits. The following are requirements established through use conditions that are the same for all MVAC retrofit refrigerants.

Unique Fittings

Each SNAP-approved refrigerant is required to be used with a unique set of fittings to prevent the accidental mixing of different refrigerants. These fittings are attachment points on the car itself, on all recovery and recycling equipment, on can taps and other charging equipment, and on all refrigerant containers. An adapter should not be used to convert a fitting.

Unique fittings help protect the consumer by ensuring that only one type of refrigerant is used in each car. They also help protect the purity of refrigerants. For a list of the MVAC refrigerant unique fittings see "Fitting Sizes and Label Colors for Motor Vehicle Refrigerants."


The technician must remove or completely cover the CFC-12 label and then apply a new, detailed label with specific information about the alternative. The colors for each retrofit refrigerant are listed in an EPA fact sheet titled "Fitting Sizes and Label Colors for Motor Vehicle Refrigerants." The label must show:

  • The name and address of the technician and the company performing the retrofit;
  • The date of the retrofit;
  • The trade name, charge amount, and, when applicable, the ASHRAE numerical designation of the refrigerant;
  • The type, manufacturer, and amount of lubricant used;
  • If the refrigerant is or contains an ozone-depleting substance, the phrase "ozone depleter;" and
  • If the refrigerant is flammable according to ASTM E681, the statement “This refrigerant is FLAMMABLE. Take appropriate precautions.”


  • The label must be large enough to be easily read and must be permanent;
  • The background color must be unique to the refrigerant;
  • The label must be affixed to the system over information related to the previous refrigerant, in a location not normally replaced during vehicle repair; and
  • Information on the previous refrigerant that cannot be covered by the new label must be permanently rendered unreadable.

Remove Original Refrigerant

The original CFC-12 must be removed from the system using EPA-approved recovery-only or recovery and recycling equipment prior to charging with the new refrigerant. This procedure will prevent the contamination of one refrigerant with another.

This requirement, as well as the other required system changes described on this page, means that no alternative can be used as a "drop-in." EPA does not use the term "drop-in" to describe any retrofit refrigerant.

Compressor Shutoff Switch

Some systems have a device that automatically releases refrigerant to the atmosphere to prevent extremely high pressures. When retrofitting any system with such a device to use a new refrigerant, the technician must also install a high-pressure shutoff switch. This switch will prevent the compressor from increasing the pressure to the point where the refrigerant is vented.

Barrier Hoses

HCFC-22, a component in some blends, can seep out through traditional CFC-12 hoses. Therefore, when switching to these blends, less permeable "barrier" hoses must be installed.