Thread: HyChill in 2.7 or 3.0

Originally Posted by BradC

Generally (and I say that with only the knowledge gleaned from manufacturers manuals and data sheets) a variable displacement compressor will stop at about 5% displacement.

Hydrocarbons pick up and move lubricant orders of magnitude better than r134a (which is frankly a **** refrigerant anyway and terrible with oil, which is why they need crap like PAG because it's the only oil that crap will move around).

In unloaded situations,there is also less refrigerant velocity,so oil return can be an issue.

In our game,we never have issues with oil return using R134a,there are much worse refrigerants around,such as R22,particularly at lower SSTs.
Even with 50/50 POE/Mineral oil,134a is fine.

I always thought R22 was pretty good. It'll transport any oil, it just doesn't cope with high superheats so is lousy in a LBP scenario. For A/C it's a ripper. Not as good as R290, but then different strokes.

My leak detector is much more sensitive to HCFC than HFC so I keep a bit of R22 around to pop into a system and then back up with a pile of nitrogen for those bizarre and really hard to locate leaks (where nitrogen and Big-Blu just doesn't cut it).