On Oct 25, 9:38 am, "Bob F" wrote:


If the water pressure won't do it, air is probably not the solution.

Andy comments:

A pressure fitting can be obtained from an RV supply house
which is usually used to hook an air compressor to the water
system to winter-proff an RV by clearing out the lines. They won't
drain on their own and all the water needs to be taken out.

This technique can be used on a house using the following
method.

1) Turn off the main water line into the house
2) Hook the pressure fitting to any ourside faucet, You
may need a female-female adapter.
3) Hook the air compressor up to the Schrader valve on
the pressure fitting. Any air compressor can be used,
including those little hand portable types that we carry
in our cars. The air volume rate doesn't matter much.
4) Turn on the water heater drain. Now, instead of 4 or 5 psi
forcing the water out, you will have 30-40 psi forcing it
out. If the water does not contain rust or rust particles,
you might as well stop. If the water starts running clear,
you can stop. No further rustandjunk will be coming out.

So, that's how one would use air pressure to speed up the process,
and , possibly, to blast thru a small stoppage at the drain valve.
If nothing comes out the drain valve at all, use the previous
poster's idea of reverse flushing. To do this, turn off the
inlet valve to the water heater and open a hot water tap
somewhere. This will reduce the pressure inside the heater
to zero, and allow the flushing hose to force water into it.

Just think it through. It ain't rocket surgery, but it ain't
always
obvious, either.

Andy in Eureka, Texas