Phisherman wrote:
On Mon, 17 Aug 2009 10:12:51 -0400, "Stormin Mormon"
wrote:

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.


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 bleach is to PREVENT the algae.