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brimhack 07-07-2010 05:38 AM

Inaccessible AC Drain line
Howdy, all.

I've got a clog in my AC drain line, but the trouble that I'm having is that the drain line empties in an inaccessible location. It drops down through the wall and is connected via PVC pipe to the drain line of a bathroom sink.

I'm a bit reluctant to try to use a shop-vac to pull out the clog through the T in the drain-line, but is this my only other option?

I can send some pictures if those would aid in the description. Let me know, thanks!

CraigFL 07-07-2010 05:56 AM

I blow mine out with pressure from my air compressor every so often. I keep the pressure below 40psi when I do it...

brimhack 07-07-2010 08:06 AM

I tried doing that through the access "T" in the drain line, but rather than loosening the clog, it just blew air straight back into the condensate pan.

Although I suppose I could cut a section of the drain line after the "T", blow the air in there and then put the whole thing back together.

CraigFL 07-07-2010 09:09 AM

You need to seal the tee off so it only blows through the drain line. I have a short piece of auto heater hose that's just the right size to jam into the ID of the drain pipe. You then need a seal so that you just don't blow air down the hose but have it sealed off so you actually pressurize the line to force the clog out.

brimhack 07-07-2010 11:08 AM

I tried to a diagram of what my setup looks like...

The problem I have, even when I have a strong seal around the compressed air hose, is that there's no chance for the drain line to get pressurized: it just blows out the end that drips into the condensate pan. And I just now realized that the same problem would apply with a shop-vac.

Unfortunately, there's no access to either end of the drain pipe. The insides of the AC unit are sealed so I can't access the section that ends at the condensate pan, and the other end drains into the bathroom sink drain line.

kok328 07-07-2010 03:23 PM

Have you tried a plumbing snake or an electrial fish tape?

oldognewtrick 07-07-2010 08:38 PM

Armchair quarterback, oldog/newtrick thinks KOK has the right idea, or cut the pipe after the tee and put some pressure there.

Unfournately I understand your diagram.... oh so well...sigh...

brimhack 07-14-2010 10:00 AM

The snake seems to have done the trick, knock on wood! Thanks for the help, fellas!

inspectorD 07-14-2010 01:54 PM


Originally Posted by oldog/newtrick (Post 46428)
.Unfortunatly I understand your diagram.... oh so well...sigh...

You mean the part about the clog and the commpressed air?? Does that upset your wife too?:o

Glad you found the fish...and cleaned your pipe.;)

kok328 07-14-2010 03:22 PM

Job well done! ;)

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