George wrote:

On Tue, 12 Dec 2006 13:58:44 -0500, Jeff Wisnia
wrote:


George wrote:


Our house has a "Craftmaster" gas water heater (c 2000), which acts like
it has a broken dip tube - the hot water is lukewarm, even though the
gas does come on from time to time.

I removed the inlet pipe. I can see (and feel) what seems to be a black
plastic hose extending down from the inlet nipple. It doesn't feel at
all free.

1. Do I need to remove the (galvanized) inlet nipple to get the tube
out?

2. Inside the tube, there was a plastic strip, about 4" long, with two
magnets in it. It was a snug fit, but it pulled out without excessive
force. What is this?

TIA,
George

Yes, you have to remove the nipple, then the dip tube will pull out.

The plastic strip with magnets sounds like it could be part of an
anti-thermosyphon valve in a "heat saver nipple" used to prevent warm
water (which is less dense than cold water) from climbing upward into
the uninsulated pipes and wasting a little energy during long periods
when hot water isn't being used.


Thanks for that. The nipple thing is still confusing. It looks a lot
like it's really part of the tank, based on the color and the shape.
And, it's recessed below the sheet metal - so much so that I don't see
how I could get a pipe wrench on it.

Might there be some other construction here?

Thanks again,
George

Sorry I misunderstood what you were describing as the "inlet nipple", I
thought you meant a male-male nipple about three inches long, often
located between the lower half of a pipe union and the tank boss.

Sound like it's got one of those plastic dip tubes which can be "damn
near impossible" to remove.

Before you go nutso over it, have you ruled out a thermostat problem?

With the tank full and that inlet disconnected, after the burner shuts
off, If you drain water from the clean out hose bib at the bottom of the
tank is the water which comes out hot or warm? If it too is only warm,
I'd look for a problem with the thermostat before accusing the dip tube.

HTH,

Jeff
Jeffry Wisnia
(W1BSV + Brass Rat '57 EE)
The speed of light is 1.8*10^12 furlongs per fortnight.