Automotive Air Conditioning Information Forum

Hi -

I have a '97 Chevrolet Sierra whose a/c condenser sprang a leak many months ago, so there's no doubt the refrigerant is long gone. But what happens to the oil in this case? Is it in solution or suspension with the refrigerant, so it disappears as well, or does it separate out and remain in the system? If it remains, will the vacuum evacuation get rid of it? I'll be replacing the condenser (and several other parts, of course), and I'd like to know if I need to allow for some old oil already in the system.

Thanks --

Mark W.

ttiwkram wrote: ↑Sun Jul 04, 2021 8:35 am
I have a '97 Chevrolet Sierra whose a/c condenser sprang a leak many months ago, so there's no doubt the refrigerant is long gone. But what happens to the oil in this case? Is it in solution or suspension with the refrigerant, so it disappears as well, or does it separate out and remain in the system? If it remains, will the vacuum evacuation get rid of it? I'll be replacing the condenser (and several other parts, of course), and I'd like to know if I need to allow for some old oil already in the system.

Some oil will be discharged with the leaking refrigerant.
Some will remain behind, but now possibly contaminated since the system has been left open to atmospheric air and moisture (the oil likes to soak up water vapor ie hydroscopic.
Evacuation will not remove the oil.
The rest of the components should be flushed once the condenser is out for replacement

Interesting! Thank you.