Blowing drains

[Stormin Mormon]

Once in a while, I have need to clear a clogged drain line from an AC unit. Now, is one of those times. I've got a maybe job. We'll know in a couple days if I have the job or not. Big system, 8 ton unit. The building has a couple 12 ton and five eaches 8 ton AC. The drain line is about an inch or 1 1/4 inch copper, with a vertical open top tube to pour in some cleaner, or insert a blow gun tip. The drain which is clogged is about 10 feet long, with maybe 3 elbows invovled. Drains onto a rolled black rubber roof, so I'm not eager to use chemicals.

Compressor and blow gun tip comes to mind. What other options are there? My parts house has a little thing with a carbon dioxide cylinder. Wonder if that's big enough.

Back in the good old days, we'd use a tank of freon to blow it out. That's no longer done, of course.

[The Daring Dufas]

I use a shop vac on drains. No splatter.

TDD

[Ralph Mowery]

I have used a wet/dry shop vacuum to suck out the drains from the open end.

[Don & Lucille]

[HeyBub]

Easy enough to find out.

Portable compressed air tank is another possibility.

Another possibility is prevention: You can spend more than pocket-change to buy these anti-biologic pellets to drop in the condensate pan (they last for a season) or dump a cup of bleach in the same pan.

[Paul Franklin]

If you can get a garden hose up there, use a drain king. It's a rubber device you attach to end of hose and slide into end of pipe. When you turn on the water, it first expands to seal against the sides of the pipe, and then releases water pressure into the pipe.

I've used them many times to clear undersink drains. Works like a charm. Come in different size ranges.

HTH,

Paul F.

[The Daring Dufas]

I have a couple of interesting gadgets that Johnstone used to carry. The things are machined aluminum holders for the small CO2 cartridges and have a 3/4" male pipe thread on one end with a pair of small holes. You insert a CO2 cartridge, screw the adapter on to the pipe, then twist the holder tight which punctures the gas cartridge. It works fairly well for some clogs.

TDD

[bob haller]

why not replace the line with a soild piece of flexible plastic pipe? go large like 2 inches and never have the problem again

[Phisherman]

I have a compressor but I use a garden hose to flush it out with tap water. I had been advised to use bleach in the lines, but never tried it because the water flush does the job.

[The Daring Dufas]

The HVAC supply houses actually carry a clear plastic condensate trap kit. It even comes with a sort of bottle brush for cleaning.

TDD

[HeyBub]

Not really necessary; the algae clog is VERY slight - more like a spider web in strength. If you can wrap your lips around the pipe, you can blow it loose (don't suck).

[HeyBub]

The bleach is to PREVENT the algae.

[Roger Shoaf]

I have two suggestions.

First you can use a snake.

The second option is to disassemble the line and clean each piece. It is a ten foot run so this would mean one or two repair couplings to put the sucker back together and that way you could clean the sucker out with a broom stick.

[Stormin Mormon]

I did consider that. The drain is rigid, so a shop vac on the outside end might do the job.

[Stormin Mormon]

There are seven air handlers. Four of them are relatively easy to reach with a garden hose. The other 3 would need to snake a hose over carpeted area to get to the air handlers.

[Stormin Mormon]

I havn't really looked, how dificult it is to get to the pan. But, bleach is an idea. Make the whole church smell like a swimming pool. I think I better think it out again. Tablets are sounding better.

Bleach in the drain would likely not make the church stink.

[Stormin Mormon]

I know of the device you mean. The one with the rubber expanding ball that clogs the drain, and reduces back flow. That's a totally excellent idea. I'd not thought of that. Thank you.

[Stormin Mormon]

I saw that drain blower, from Johnstone. The cartridges are about two bucks each. But, it's a lot lighter than an air compressor. I could much more easily carry it up the ladder, also.

My plan at the moment is to use small compressor, length of air hose, and a blow gun. Stick the blow gun into the clean out, wrap with a towel, and squeeze the handle. Some of the air will of course blow into the pan. But, much should blow down the length of the drain. The drain is huge.

I'm wondering if wasps have nested in the open end. Need a big nylon sock or something to keep the wasps out.

[Stormin Mormon]

1) I don't have permission to replace the drain 2) drain is betwen the air handler and the wall 3) would need a hammer drill to make a two inch hole through the wall 4) Wasps can nest in a two inch pipe, also

[Stormin Mormon]

I suspect the water does a much better job. Actually, the three which are not garden hose accessable, they run just fine. I may just carry up a funnel and some bleach and hot water, and just bleach them.

Good idea, thank you.