AC Condensor Flush
Thread Starter
Burning Brakes
Joined: Oct 2006
Posts: 977
Likes: 703
From: Port Orchard, WA
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St. Jude Donor '25
AC Condensor Flush
Getting ready to replace the AC compressor, accumulator and orifice tube on my 2000 C5. I've been reading through C5 AC threads on the forum for some time and they are of great help. This project looks to have a few challenging tasks that I'm hoping for a bit of good luck with.
One thing I'm still not clear on is flushing the condensor. How much of a mess is this going to cause? Is this done in the car with the lines hooked up or not - or does it need to be removed from the car to flush?
One thing I'm still not clear on is flushing the condensor. How much of a mess is this going to cause? Is this done in the car with the lines hooked up or not - or does it need to be removed from the car to flush?
Pro
Joined: May 2013
Posts: 740
Likes: 82
From: MN
I flushed it with the aerosol can, available at most parts stores: http://rechargeac.com/products/ac-chemicals/ca-1
I did the condenser off the car, the evaporator on the car, both directions, then blew them out with compressed air before reassembling and pulling vacuum.
I did the condenser off the car, the evaporator on the car, both directions, then blew them out with compressed air before reassembling and pulling vacuum.
Safety Car
Joined: Jul 2010
Posts: 3,888
Likes: 382
From: Chandler AZ
"In a serpentine-style condenser, there is onlyone path the refrigerant can follow so theflushing chemical will follow the same path from the entrance to the exit. In a parallel flow condenser, the flush may not flow through all the tubes if some are partially or completely blocked."
I looked on Rock Auto, found part numbers, then found a new condenser coil on Amazon for about 80-90 bucks last summer.
This was while replacing a failed compressor.
Used loan a tool for flush gun from AutoZone, and bought the flush solvent there too, it had a orange/citrus scent.
Flushing evaporator, it made a mess, stuff bounced out of old empty water bottle I was using trying to catch it, too much pressure.
I would use old towel, maybe zip tied onto outlet of pipe, make a pocket/bubble space out of towel so it has room to blast out, vs just pushing towel up against the pipe, where A/C hose bolts, if was to do this again.
Supposed to flush backwards, so put flush gun in pipe that normally bolts to drier tank.
I flushed that way, and the other direction too, then again backwards, the quart of solvent got used up pretty quick, thought of buying more, but didn't.
After done flushing, I blasted out the evaporator with nitrogen, most use their air compressor, but I had nitrogen, so no chance of any compressor oil ending up in my evaporator, probably just me being OCD.
The garage had that smell for a while, after job was done I user a spray bottle of water and sprayed it all over where the solvent spattered, right side of engine, firewall, battery tray area.
Using towel to catch at ends ofpipes may prevent this.
I flushed a/c pipes and hoses out on driveway, holding them up, spray from top and let it drain out bottom end, into a bucket, you don't need much solvent, just a quick blast or 2.
I looked on Rock Auto, found part numbers, then found a new condenser coil on Amazon for about 80-90 bucks last summer.
This was while replacing a failed compressor.
Used loan a tool for flush gun from AutoZone, and bought the flush solvent there too, it had a orange/citrus scent.
Flushing evaporator, it made a mess, stuff bounced out of old empty water bottle I was using trying to catch it, too much pressure.
I would use old towel, maybe zip tied onto outlet of pipe, make a pocket/bubble space out of towel so it has room to blast out, vs just pushing towel up against the pipe, where A/C hose bolts, if was to do this again.
Supposed to flush backwards, so put flush gun in pipe that normally bolts to drier tank.
I flushed that way, and the other direction too, then again backwards, the quart of solvent got used up pretty quick, thought of buying more, but didn't.
After done flushing, I blasted out the evaporator with nitrogen, most use their air compressor, but I had nitrogen, so no chance of any compressor oil ending up in my evaporator, probably just me being OCD.
The garage had that smell for a while, after job was done I user a spray bottle of water and sprayed it all over where the solvent spattered, right side of engine, firewall, battery tray area.
Using towel to catch at ends ofpipes may prevent this.
I flushed a/c pipes and hoses out on driveway, holding them up, spray from top and let it drain out bottom end, into a bucket, you don't need much solvent, just a quick blast or 2.
Last edited by 1999corvettels1; Jun 7, 2019 at 03:30 PM.
Pro
Joined: Feb 2013
Posts: 535
Likes: 92
From: Raleigh NC
"In a serpentine-style condenser, there is onlyone path the refrigerant can follow so theflushing chemical will follow the same path from the entrance to the exit. In a parallel flow condenser, the flush may not flow through all the tubes if some are partially or completely blocked."
Thread Starter
Burning Brakes
Joined: Oct 2006
Posts: 977
Likes: 703
From: Port Orchard, WA
2025 C2 of the Year ('64-'66) Finalist - Unmodified
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St. Jude Donor '25
Thanks for the replies. Flushing went well - I left the condensor in the car and containing the mess was managable. I went with 1999CorvetteLS1's suggeston and loosley tied clean rags at the messy end.
Question: When I flushed the evaporator, a lot of oil seemed to come out with the flush solvent at first. Is this normal?
Question: When I flushed the evaporator, a lot of oil seemed to come out with the flush solvent at first. Is this normal?
