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Air Conditioning, R12 vs 134A

What's the difference?

134A was designed as replacement for R12 (used in vehicles for decades) that would not destroy the OZONE layer. The overall working properties are within 5 to 20% of R12. The majority of the time the new 134A will work just as well as the old R12. We still carry R12 to keep the purists happy.

The disadvantages of the new 134A are:

  1. The molecules are smaller so it may leak out quicker.
  2. TThe high side pressures works higher so it may wear down the compressor quicker, especially in higher ambient temperatures.
  3. TIt is not as efficient at higher ambient temperatures so it may not “cool” as well by 5 to 20%, especially when driving slower.
  4. Now this aspect is the one that drives me crazy! It is harder to detect leaks in a 134A system than the old R12 systems. Not impossible (for other shops it seems to be), just tougher, especially the leaks that take 6 months or more to leak out.

Good news, the advantages are enough to be happy with and outweigh the bad.

  • First, it is readily available, unlike the old R12 that many shops no longer carry.
  • Second, it is less expensive than the old R12 by at least 50%!
  • Third, we love the new stuff! It's a little harder to work with and separates the men from the boys!

There are several other aspects of the 134A that we deal with but that is why we are here for you providing Auto Air Conditioning Repair Services.


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