On Fri, 02 Oct 2009 15:33:12 -0400, gfretwell wrote:
My bet is the bottom of that water heater is slugged solid with scale
and you will be buying a new one soon enough. At least do it on your
own schedule.

Good call there, by the way. Wasn't getting much scale out of the drain
valve, so I'd figured it couldn't be too bad. Then I took the drain valve
apart, and the internal valve passage is a square-section s-shape, and
only of about 1/4" diameter.

I took the upper element out and had a peek inside, and it was choked
with scale at the bottom, like you figured. Not surprisingly, a lot of the
bits are far too big to ever stand a chance of getting through that valve
body...

I managed to break some of it up, probably got about 3 gallons of
solid scale out of it and another of sludge; I think that might drop the
level below the lower element (just waiting on it to heat right now)
which will buy some time, but it's looking like a new heater's a good
idea sometime soon :-)

cheers

Jules