"Gunner" wrote in message
...
On Sun, 11 Jan 2004 01:05:22 -0500, "Blake Loyd"
wrote:


"Gunner" wrote in message
.. .
Ive got a problem with a water heater at work. This is a natural gas
unit used to boil water out of oil for reusing the oil

Turn off the gas, turn of the power, wire the solenoid directly to the
transformer, turn on the power. Does the solenoid hold in? If not it's
a
bad transformer or solenoid. If it does your flame sensor is bad. My
bet
is a bad winding in the solenoid or transformer that shorts or opens
under
its own induced field.

Loyd

Blink blink..ok....Ill try that. Ill also try that with the gas on at
the appropriate time in the ignition cycle and see if the flame rod
ever stablizes or has a rectification.

I should have said the flame sensor circuit/system.
Now, I am assuming that you haven't changed out the controller, because
if you have and you have an external purge timer you just need to read the
installation instructions regarding that situation.
I am also assuming that the controller hasn't gotten wet as that could
cause problems.
That said, maybe this will be clearer.

Turn off the gas. Turn off the power.
Check the flame sensor wire to make sure it is not damaged and that it isn't
touching anything to which it can ground out. If it appears ok then check
the following.
Mark the wires so you can reconnect them in the same manner as switching
leads may cause the system to lock out. Disconnect the secondary of the
transformer from everything. Disconnect the gas valve. Wire the transformer
directly to the gas valve solenoid. Turn on the power.
Does the gas valve open and stay open or does it chatter(open close open
close open etc)?
If it opens and stays open the transformer and valve are fine.
If it chatters then one or the other is bad. Since you say the 24V is
constant it is apparently the solenoid.
If the transformer and gas valve solenoid are good then the problem lies
in the flame detection system/circuit.
Turn off the power.
Rewire the transformer and gas valve as they were originally. Loosen and
retighten the flame sensor mounting screw. See if that solves the
problem(bad ground). If not, remove the flame sensor, disconnect it from
the controller at the controller, attach meter to lead end disconnected from
controller and base of sensor(ground), heat sensor with a propane torch to
see if it produces the 0.8uA minimum through the lead.
If it doesn't, disconnect the lead from the sensor and test the sensor
again to see if it produces the 0.8uA minimum. If it does the lead is bad.
If it doesn't the sensor is bad.
If both check out as working properly and you are confident that the
moving of the lead hasn't just happened to alleviate a ground in the lead,
then the problem lies in the controller(unless you did alleviate a ground in
the sensor lead).
From your description of what's going on it sounds as if the problem
lies in the solenoid circuit. It could be the solenoid or it could be the
controller isn't holding in the solenoid circuit. Since it happens during
the start-up I doubt it is the flame sensor. I guess is that it is the
solenoid or the controller.

Loyd