On 1/14/2016 10:40 AM, Snuffy "Hub Cap" McKinney wrote:
I have seen these gadgets that use air pressure for drain pipe blockages. I
can see that could be useful where there are too many elbows in a small
diameter pipe for a regular snake. Anyone have experience using pressure
like this?

First thought I had was that all the other drains might need to be plugged
first. And also what's a reasonable high pressure limit?

I have had this trouble with a 1-1/2 inch washing machine drain, where there
are 4 elbows before it gets to the main house drain. I was able to clear
out part of the piping with a small diameter snake, but not all. Eventually
got it cleared out alternating boiling water, then flushing with hot water,
then drano, water flush, snake, etc. Also make a tight connection from the
hot water faucet to the 1-1/2 standpipe and ran it until it flowed normally.
All this worked, but it took a lot of time.

I have some devices that use water pressure to that end.
They have a place for a garden hose to be attached. They
are then inserted into the drain. The water pressure expands
their outer diameter until they fit snuggly in the drain opening.
The water coursing through them then pushes any obstructions out
of the drain.

The biggest issue with these are the typical vents associated with
most drains. These must be plugged lest the pressure never develop.
Note where the drains vent in your tub, sink, etc.

Things similar to:
http://www.amazon.com/G-T-Water-Products-186-Attachment/dp/B0000CBIWC

I have a couple of different sizes.