Refrigerant change overs

[Superteck]

Does anyone have the skinny on r422b (NU-22B) and any downsides of longterm use? I have been informed that the industry is wanting to use
R407c on equipment that cannot be completely changed out for use with R410a. I was under the impression from the deputy directors speech at the Vegas Esco meeting that NU-22b, hot shot and one shot etc.... would all be temporary fixes. any ideas.

[BaldLoonie]

NU22b is an HFC so its future isn't affected by the HCFC phaseouts. It has a slight capacity reduction, less so than NU22 however. According to my buddy at ICOR, they've had great success with both of them. There are some large firms, namely European based, that wanted to go green but couldn't get units with R410a in them at the time. So they bought new stuff, the one here in town had big Choo Choo rooftops, sucked 22 and put NU22 in them. Technically that voids the warranty but I bet even if the comp goes back, nobody is going to do an expensive test to see what gas was in it! My buddy is running the 2.5 ton A/C I sold him on NU22b since it came out. The unit was marginally sized anyway but apparently is doing fine.

Hot Shot is 50% R22 so probably would be considered temporary. Not sure about One Shot.