hot water

[billy1davis]

Hot water heater not working on propane. Does work on electrical just fine. Light at switch to turn hot water on doesn't light up and it use to. Can't smell propane coming out of tube where it feeds into the tank. Trailer is a 2003 Komfort.

[billy1davis]

It is now working . Thanks to all that helped me. Here is the test that came from a local RV shop that was the quickest and narrowed it down to the real problem very easily......Simply run a 12 volt line from the battery directly to the valve. If the valve opens then you know it is the board. If the valve doesn't open then it is the valve. By the way one can hear the valve open..no need to try to smell. Hopefully this info is helpful to someone else.
It would seem to me that the same test would work for all of the gas fired appliances.I know I will certainly remember this one.

[Bonefish]

Power to the valve, gas to valve....do you smell propane when it tries to light?

Did you clean the burner tip and make sure it was not plugged up?

[billy1davis]

OK I have replaced the gas valve. Still not burning. Same problem and facts. Have volts to the brown wire while trying to light. Have gas to the top of the valve. No gas out of the bottom of the valve. Have good ground. Must be the mother board? But what is going on with the board if i have 12 volts while tryiing to light? Help

[BrianinMichigan]

I had one of the coils open in mine. It was around 85 ohms. I bought some magnet wire from McMaster Carr and rewound it myself. Cost was around $13 with shipping for the wire. That was about 4 years ago all is still working fine.

[gkainz]

Old-Biscuit wrote:
One thing to check.......

Main gas orifice......make sure it isn't plugged

Thanks! 4 pages before the obvious (to me, anyway!) Unless I'm the only one continually plagued with propane-loving spiders! 🙂

[Old-Biscuit]

One thing to check.......

Main gas orifice......make sure it isn't plugged

[billy1davis]

ok I have a good ground to the black. I do have the power to the valve when lighting. Sounds like a bad valve to everyone? Thanks I will order one!!

[jamnw]

As "old biscuit" said, the 12V is there to energize the solenoid and provide gas. You don't want that solenoid energized all the time or BOOM!

Did you test the black wire/ground on the solenoid? You can check it with a meter on resistance mode.
Put one lead on the black wire connector, and the other lead on a metal part of the trailer.
You should see a short/zero ohms.

Doesn't matter which lead goes where. Make sure you have a good contact point to the metal to test the continuity of the black wire.

At this point you have it down to the solenoid or a poor ground.

[billy1davis]

Thanks. I will be away for a day or so. I hope you will be around to help then

[Old-Biscuit]

12V on brown wire when sparking (for about 6-7 sec.) then if NO FLAME the board shuts down.

If FLAME the board continues to hold 12V on solenoids keeping them open.

The spark electrode is used as flame proving. When gas lites off a millivolt signal is induced thru flame ionization and goes back to board via spark electrode wire.
This millivolt signal is what allows the board to hold 12V on gas valve solenoids.

12V power on brown wire to solenoids........good spark.......no flame
Points back to bad solenoid(s)

Test the resistance of each solenoid one at a time.
Remove both wires from solenoid
Install meter leads...black in 'Com' and red in 'ohm'
Set voltmeter to ohms
Touch leads to terminals on solenoid

[billy1davis]

I just completed the test outlined by jamnw. I have power at the brown wire only when it is trying to light. It is dead otherwise. Should there be 12volts at the brown wire all the time when it is on? Not just when trying to light off?

[jamnw]

From looking at the schematic for a suburban DSI.

Pull the brown wire off the gas solenoid. Hook one lead of a volt meter set to DC volts to the brown wire, and the other to the trailer frame.

Have someone try to turn the heater to propane while you watch the volt meter. If you get anything around 12VDC your board is good and the solenoid in the gas valve is probably defective. OOORR you have a poor ground on the other wire which should be black.

You can double check that by adding a new wire to the black side and make sure it is grounded out to the trailer. Try turning it on again and see if you get gas.

[billy1davis]

I do have power to the valve, however is only when the HW is trying to light, I have 12 volts there as it is lighting but no volts there when it is not lighting. I tried shorting one valve and then the next and no gas. So the board is good and the valve is stuck?

[jamnw]

Isn't the light by the switch an "attention" light? Its supposed to let you know that the propane is turned on, but nothing is happening?

You could ground one side of the gas valve to see if the solenoid is working. I would only do that for a moment to make sure gas flows. If it does that rules out the valve, and points to a malfunction on the board.

It could just be some dirty contacts on the board. I would also try to take each off and clean with an emery board/lite sand paper.

Or, a cold solder joint on the board which is causing an intermittent open in the joint. Moving the board around is wiggling that joint causing the light to go out.