On Mon, 6 Jul 2009 16:10:31 -0500, "HeyBub"
wrote:

LouB wrote:
I happen to be standing near the electric hot water heater while the
dishwasher was running. Hear noise like "rattling". Something to
worry about or just normal? Ideas please?


Bubbling, like boiling water.

A drain and flush of the water heater can't hurt. This will probably remove
a bunch of sediment that's usually the cause of the gurgling.

You know, I think it depends on what time of day one posts, which set
of people reply. At any rate I've read a lot of reports here of
opening the flush valve and it clogging with sediment and couldn't be
shut again.

And in my case, I'd had an 8 year water heater for 8 years and
something was wrong with it, and before I threw it away I cut it open
and found maybe six flat tablespoons of sediment in it. A half inch
deep at the center of spherical bottoom. At that rate I had at
least 120 years before it hit the electric element. I don't use a lot
of hot water, but still. I live alone, laundry on warm, dishwasher
sometimes, but I take a bath in a full small-to-medium sized bathtub
every day.

Of course that means I wouldn't have clogged the drain, but there are
a few inches above the drain until it gets to the element when it
could clog.

I can see why sediment at the bottom would cause boiling at the bottom
of a pot on a stove, and subsequent noises, but since the electric
element is several inches above the bottom and above all the sediment,
why would sediment cause gurgling? Not that it doesn't happen, but I
don't get it.