When hydrofluorocarbons (HFCs) first came onto the radar screen a decade or so ago, we learned several things rather quickly:

  • Those refrigerants would not work with mineral oil that had been the oil of choice for chlorofluorocarbons (CFCs) and HCFCs.

  • The first HFC to come to market would be R-134a and the first place it would be used would be automotive air conditioning.

    And that would be it ... and we could go on from there. Well, not exactly.

    It ends up the ‘no mineral oil' and ‘R-134a in automotive' decrees were not etched in stone. And in fact, things are underway to contradict those declarations.

    THE MINERAL OIL ISSUE

    At least two refrigerant manufacturers have introduced HFCs that they say work with mineral oil. The companies are backing them with their technical expertise. There are about a half dozen or so of such HFCs.

    At present, they are earmarked for aftermarket applications with one common approach as a retrofit option for equipment originally designed to operate with HCFC-22. With R-22 facing phaseout, this retrofit is seen as a way of extending the life of that equipment and also giving the end user a bit better ‘environmentally correct' label since HFCs have a lower global warming potential than HCFCs.

    At this point, the HFC/mineral oil mix appears to be an aftermarket dynamic. OEMs continue to advocate HFCs formulated to work with synthetic POE oils. Such refrigerants for use with POEs are the now familiar R-404A and R-507 in refrigeration and R-410A in air conditioning. There are others, but those are some of the main players.

    THE AUTOMOTIVE ASPECT

    At the same time, at least two refrigerant manufacturers are looking at options for automotive air conditioning other than HFC-134a. HFCs do not have the GWP of HCFCs, but there apparently is enough of a GWP issue with HFCs to bother some environmentalists in Europe. The HVACR industry in Europe has so far fought a successful battle to preserve HFCs for stationary equipment, but a few years ago did give ground to environmentalists by agreeing to phase out HFCs in automobiles that are used in Europe.

    First thought went to using CO2 as the alternative in auto air conditioning, but now the manufacturers involved in the research are looking at other options, which so far are quite proprietary.

    WHAT TO THINK

    The two thoughts that come to mind are:

  • Will HFCs that work with mineral oil ever become an OEM option?

  • Will the ban on HFCs in automotive air conditioning in Europe ever reach North America?

    At this point, neither seems to be happening. But I'm not about to get out my stone etcher to affirm that.

    Peter Powell, Refrigeration Editor, 847-622-7260, 847-622-7266 (fax), peterpowell@achrnews.com

    Publication date: 04/03/2006