"HRL" wrote in message ...
"Robert Spike" wrote in message
om...
I just had a new hot water heater installed a week ago. The plumber
recommended an Expansion Tank, and he installed one of those as well.

Everything is fine. However, once my shower is turned off, or a
toilet is flushed and fills back up, I still hear water flowing
through my pipes through out the house for about 30 seconds or so.
Nothing is leaking anywhere, and this behavior did not exist before
the new hot water heater and new Expansion Tank were installed. My
plumber is baffled. He came out and replaced the Expansion Tank
(thinking that was the problem) but it hasn't helped.

Any idea why this is happening? Is it the new Expansion Tank and, if
so, is this normal behavior?

Please feel free to post here, or e-mail me directly at
.

I am baffled why the plumber doesn't know.
Why did he recommend the expansion tank unless you had low water flow?
So now that you have the expansion tank you should get more flow with the
extra supplied from the tank. But after you turn off the valves it takes a
while for it to fill again. If there is a way to turn off the line to the
expansion tank I expect turning it off would eliminate the problem.

If the sound itself is exceptionally loud that is something else.


So - - - to confirm what I think I understand here. The sound of the
water rushing through the pipes for 20 seconds or so *after* the
shower/sink/toilet shuts off is actually normal as the water is
refilling itself back up into the Expansion Tank? I actually know
absolutely nothing about plumbing, so all this information is very
helpful to me.

I'm not sure why the plumber recommended this for me. It was pretty
inexpensive, and I recall having one put on in my last house (in the
same Township) after the water company installed a "back flow" device.
But, this behavior didn't exist in my old house - - - Just my new one
since 6 days ago when the new water heater and Expansion Tank was
installed.

I'm just trying to reach a conclusive decision and feel comfortable
that my house isn't going to flood from a pipe burst.

Thanks, again. I'll look forward to further responses.