And no I didn't really need to charge it. Just thought it wasn't super cool, even though it was probably as cool as it will get.
Yeah, I've been googling around a bit and they say the PAG oil (the oil that my "all-in-one" charger had) DID NOT immediately cause voltage problems in a Prius's compressor (which is similar to a Volt's). The tester said he took a 95k mile Prius, drained its compressor oil and used PAG in its place, and drove it 8k miles with no apparent problem (but he then took the PAG out and switched back to the Prius certified oil to be safe). So I should be OK for a while but this was so dumb on my part. The A/C was working more or less fine just not completely freezing.Yep, I also read that you can't use the small cans of 134a at the auto parts store either since they contain a small amount of oil, and that you must fill with a 30# cylinder. I have a fair bit of automotive a/c experience, including complete rebuilds but the warnings on the Volt system have left me to just decide any work will get done with the dealer.
I did the dealership's flush using the GM a/c flushing machine. It takes out all of the freon gas and adds freon + oil back in, I think. As I understand, most of the oil "travels with" the freon, so most of the old oil was taken out. The dealer didn't really know much about it other than to say "we connected it to the GM machine it took everything out and added new freon back."The Volt uses a variable output compressor, and often is not running at full cooling capacity. My 2013 can get pretty darn cold when it wants to, so I just let it do its thing. If you got the wrong oil out after only a short time you're probably OK. Takes a while for the insulation to break down. A similar thing can happen in HVAC compressors if the refrigeration system is not evacuated well enough after brazing fittings together, or they aren't brazed with a nitrogen purge. The residue inside the copper lines eventually damages the compressor's insulation as it forms an acidic compound. Can take years though.
I'm pretty sure that's what he did? He did the standard GM a/c service using the GM a/c machine which sucks everything out, flushes the system with something, and adds new stuff in. Regardless, this GM service station said they can't really do anything more. It'll probably be fine.Your mechanic should have removed all the Freon, pulled vacuum, and added exact amount of Freon using weight. I would not do anything else for the variable speed compressor with TXV valve... Charging by pressure is not a wise thing to do. And - get pure Freon without oil or any additives. It is not too late to do the procedure I described - better than replacing $2k+ compressor down the line...
My last car was a luxury convertible whose a/c was so freezing cold you could feel cool-ish with the top down in a 90 degree day. They must have done something special with that.I don't think 55 out of the vent is an unreasonable figure. With 134a you generally won't see less than about 37 inside the evaporator. By the time the temperature is exchanged through the evaporator to the air, and to the vent opening you'll have even more loss of temperature. Granted this is normally on a 80-90 degree day. 100+ likely won't see less than about 65 out of the vent, possibly higher if the battery is also drawing from the A/C system. Truth be told though, most modern day A/C systems are VERY particular about charge quantity. a couple ounces over or under results in severe loss of cooling capacity. Most modern systems use 2 pounds or less. Not like the old R-12 systems that held 4 pounds and were much more forgiving with over or under charged systems.