- Make
- Saturn
- Model
- SL2
- Year
- 1995
- Miles
- 250K
- Engine
- 1.9L DOHC
I hope to get some useful discussion, but expect to get some blasts, too. I will try to keep "thick skinned"!
I have read hints that R-290 (propane) can work well in place of R-134a; but is illegal here in USA due to fire danger. Being a curious soul, I wanted to try anyway...
It is a '95 SL2 and the A/C has not worked for many years. No known damage, but just stopped cooling and it isn't my primary SL2 so I figured to never bother fixing the A/C. Nothing to lose, right?
I connected the gauges, no pressure in system, so I pulled a vacuum and it held fairly well. So, I charged it with barbeque propane; left the PAG oil in there.
Cooling does definitely seem good. I can get 20-30F at the dash outlets. The low-side line into the compressor has frost on it, even with hot air from the radiator blowing on one side of that line and the exhaust manifold about 6" away on the other side. Pressures are different, of course. I settled on 300-350 psi high with the low staying fairly constant at 20 psi. I tried varying the charge a lot, going up high enough that the compressor was cycling on/off from the high switch (about 400-450 psi); that 300-350 seems to be best so far. With propane, I had no qualms about adding/bleeding to try a lot of different pressures.
So, I'm trying to decide now if I should go ahead and flush all the PAG and replace with something that is compatible with propane and R-134a (POE?) and recharge with real R-290. I don't really need working A/C in this car, but would sure like to prove out a replacement for R-134a; especially since it seem to cool so much better!
PS: I figure the charge I have in there is about equivalent to 1 qt of gasoline, and would have to get "trapped" just right, if released, to keep in the 2-10% flammabilty range to burn at all. I'm not too concerned about the fire dange
I have read hints that R-290 (propane) can work well in place of R-134a; but is illegal here in USA due to fire danger. Being a curious soul, I wanted to try anyway...
It is a '95 SL2 and the A/C has not worked for many years. No known damage, but just stopped cooling and it isn't my primary SL2 so I figured to never bother fixing the A/C. Nothing to lose, right?
I connected the gauges, no pressure in system, so I pulled a vacuum and it held fairly well. So, I charged it with barbeque propane; left the PAG oil in there.
Cooling does definitely seem good. I can get 20-30F at the dash outlets. The low-side line into the compressor has frost on it, even with hot air from the radiator blowing on one side of that line and the exhaust manifold about 6" away on the other side. Pressures are different, of course. I settled on 300-350 psi high with the low staying fairly constant at 20 psi. I tried varying the charge a lot, going up high enough that the compressor was cycling on/off from the high switch (about 400-450 psi); that 300-350 seems to be best so far. With propane, I had no qualms about adding/bleeding to try a lot of different pressures.
So, I'm trying to decide now if I should go ahead and flush all the PAG and replace with something that is compatible with propane and R-134a (POE?) and recharge with real R-290. I don't really need working A/C in this car, but would sure like to prove out a replacement for R-134a; especially since it seem to cool so much better!
PS: I figure the charge I have in there is about equivalent to 1 qt of gasoline, and would have to get "trapped" just right, if released, to keep in the 2-10% flammabilty range to burn at all. I'm not too concerned about the fire dange