The banning of just five refrigerants under the new PFAS regulation proposals would lead to the banning of virtually all the current lower GWP HFC/HFO alternative refrigerant blends. Excluding the current refrigerant blends that are already banned in Europe for containing CFCs or HCFCs, only 13 of the remaining 106 current ASHRAE-listed R400 series blends would escape a PFAS ban. Those 13 outside of the scope are predominantly hydrocarbon blends. Of the 500 series blends, only two, both hydrocarbon blends, are outside of the scope.
Of note in this proposal is R134a and R410a would be on the chopping block. In the US, these two refrigerants are widely used in automotive and residential applications, respectively. While this proposed ban affects Europe, there’s been similar movement in the US.
The current proposed replacements are R1234yf for R134a and R32 for R410a, both flammable. R32 is what HVAC techs are referring to when they mention that Europe uses methane as refrigerant, and I knew one tech who scoffed at the notion while he lugged around a jug of R410a, of which the same could be said.
However, I’ve been reading that the flammability is “mild”, and aiming a torch directly on a leak is unlikely to cause any serious fireworks, unless there’s a large amount of oxygen present in the system. I’ve heard tales of explosions on larger commercial systems and chillers that weren’t properly evacuated.
R410a is also labeled “mildly flammable”, which manifests in larger torch flames in my own experience.
What’s neat to me about R32 is that it appears to perform 10% better than R410a, and there’s “drop-in” replacement blends on the market, R454b appearing to the be the most promising one with similar performance to R410a. R454b is compatible with the same POE oil used with R410a, which means you wouldn’t need to clean out a lineset before switching. You should always replace the filter dryer, however.
Drop-ins are rarely that, and I’m curious if systems that aren’t rated for both might need different metering devices (TXV) or automatic leak detection.