R22 Replacement
I've been using R407C in most of my retrofits. It's best to replace all of the mineral oil you can with POE (drain the compressor). I haven't had one bit of trouble with it and the pressures are very close to R22. Never had to adjust the TXV. One drawback is the most of the modern Refrigerants are getting phased out and getting very expensive. R290a is good choice as well since that is what will replace all of these "R22" systems in the near future. Please don't mess with it if that unit has a leak though - it's obviously very flammable and therefore dangerous if you don't have a tight system. I've experimented with it at home and it seems to work just fine. I've repaired newer R290a systems which are already on the market. the world is going back to Propane, Butane, Methane, Ammonia, and CO2- so we're basically full circle back 80 years.
PS - no matter what you use, fix the leak first
|