On Mon, 17 Jul 2006 19:44:19 -0400, "HeatMan"
wrote:


"EXT" wrote in message
tanews.com...

"peter" wrote in message
news:vuwug.5313$Ss2.4793@trnddc01...
I have a gas water heater that doesn't use electricity. It works by
having
a bare copper wire conduct temperature out of the water tank into the
thermostat.

That is NOT a bare copper wire, it is a capillary tube that conducts a
liquid that is heated in the pilot light and uses the pressure to operate
the valve.


Wrong.

Good thought, though.

The Flame at the tip makes two different metals generate a very small amount
of electricity, in the milli-volt range. That electrical current is enough
to hold the pilot solenoid open. It won't open the pilot solenoid, that's
why you have to push the button when lighting the pilot.


The current is generated by a difference in temperature. A difference
that won't be there when the pilot has been off and needs to be
relighted. You need to hold the button down until the end of the
thermocouple (the one in the flame) warms up enough for it to generate
enough current.


--
Mark Lloyd
http://notstupid.laughingsquid.com

"Democracy is two wolves and a lamb voting on what
to have for lunch. Liberty is a well armed lamb
contesting the vote." - Benjamin Franklin