Quote:
Originally Posted by Piwoslaw
An 'inverted A/C system' is more or less a steam system, only with refrigerant instead of water. In this case we may use something other than water for our "steam", which would be appreciated in colder climates. But water (in a vacuum) would be OK for testing.
I'm not sure that an A/C compressor would spin when you blow air through it. The compressor probably has a one-way valve at the piston intake. Even without it, pumping air into the compressor would force the piston down to its lowest position and that's that. The compressor would need to have at least 3 pistons and some semi-complicated valve system to force air into the right piston at the right moment in the cycle. Something like a steam locomotive? Hint, hint, wink, wink 
I'm not sure about reversing the newer scroll type compressors.
Soooo.... Replace an A/C system's compressor with an air motor we're getting somewhere. |
You could be right, but If I understand correctly most automotive compressors are a swash plate style piston pump, which have a rotating orifice plate or the orifice and swash plate are fixed and the pistons and cylinders rotate together. So it shouldn't make a difference if pressure is added or made. the swash plate setup always has multiple cylinders, so the stalling you mentioned shouldn't be a problem. The scroll compressors also only has inlet and outlet ports, no valves, so I can't see any reason for it not working in revers as a motor.
The only setup i can think of that wouldn't work as a motor is if the compressor uses reed type valves like in most piston air compressors. Other wise a compressor should work as a motor if it has mechanical valves, orifice plate or just inlet and outlet like a scroll, twin screw and vane compressor.
It may be that there is many different styles in production, so its just a matter of knowing what your looking at when searching in the junk yard.
In any case I think its worth further investigation. I will try to remember to take apart different compressors next time I'm in the junk yard. (I think the innards of a scroll compressor will look good on my book shelf anyways)