R-134a is being phased out as well. R-32 or R-454b are the new coldness.[1] I believe R-12 and R-22 were phased out because of their ozone depletion potential.

R-134a is being phased out as well. R-32 or R-454b are the new coldness.[1] I believe R-12 and R-22 were phased out because of their ozone depletion potential. In the states R-134a replaced those. R-134a was great! No more ozone layer damage! But its global warming potential is still too high[2] to comply with various climate change pacts and laws (I think California has a law that will limit refrigerant GWP to 750 in 2023 [3] ). It's a bit weird for consumers though because if you're buying an air conditioner/heat pump right now then it's probably still R-134a. Who wants to buy hardware that will last for 15+ years but could cost a significant portion of the original unit price to refill in the event of a leak or installer error? [1] https://us-ac.com/usac-news/r410a-phasedown/ https://us-ac.com/usac-news/r410a-phasedown/ [2] https://www.daikin.com/corporate/why_daikin/benefits/r-32 https://www.daikin.com/corporate/why_daikin/benefits/r-32 [3] https://ww2.arb.ca.gov/sites/default/files/2020-06/January%2030%2C%202020%20Workshop%20Slides.pdf https://ww2.arb.ca.gov/sites/default/files/2020-06/January%2...