As the summer cooling season gets under way it is a good time to reiterate that flammable refrigerants should NOT be used as replacement for R-22 in existing systems. Some people are putting in R-290, which is simply propane. A few have tried charging their systems with fuel grade propane. Not only is this dangerous, but fuel grade propane has lots of water contaminants and will screw up your systems, that is if it does not blow up. Yes, it is true that the EPA approved flammable refrigerants for a few very specific uses in systems with a very limited charge. However, these are NEW SYSTEMS ONLY! These systems are designed from the outset to handle a flammable refrigerant.
Your R-22 air conditioner of heat pump has many spark creating controls, such as relays and contactors. A leaky system recharged with a flammable refrigerant could have all the components for an explosion: fuel, oxygen, and an ignition source. The EPA has started fining companies for selling non-approved, propane based R-22 replacement refrigerants. Most have “22a” in their name. Unfortunately, there are still plenty of places to buy this stuff over the internet. A few other names include “Frosty Cool” and Eco-Freeze”. You should be wary of anyone that sells refrigerant directly to consumers over the internet.
I don’t believe regular HVACR wholesalers will have any of this stuff, and major refrigerant companies such as Honeywell, DuPont, or Arkema are not selling it either. They do each offer their own R-22 replacement solutions, none of which are flammable. Some legal replacement solutions have very small percentages of hydrocarbon components to improve oil return. Their hydrocarbon components are in such small quantities that they generally pose no threat of flammability. So what is the best thing to put in an R-22 system? R-22. Read more about the EPA actions and warnings here.