Water Heater won't fire....

[Gemstone]

Electric is fine.

Checked the Suburban troubleshooting, so far I have determined:

I have spark
voltage is good
solenoid on LP valve is activating (I can hear it)

I have verified the burner tube from the solenoid is clear
I have verified the burner orifice is open
I have gas to other appliances..furnace, stove... I have to assume that there is gas being presented to the LP valve (no way to check for correct pressure)

but no gas at the orifice or burner when sparking (no gas sound, no gas odor).

To my way of thinking it could be the control board, but then again, I do have voltage at the solenoid....bad LP valve ??

Any suggestions ?

TIA
Gemstone

[Dick D]

It could be insects in the supply tube or the valve is in fact bad. Take the supply tube loose at the valve and see if you can blow through it.

[Gemstone]

"It could be insects in the supply tube. Take the supply tube loose at the valve and see if you can blow through it".

Must say, I haven't tried that....but how would insects get into a closed system ? Gas supply comes from the propane tanks to the iron supply pipe, then copper tubing from iron pipe to the valve...am I missing something, where would the insects get in ?

Thanks for the reply
Gemstone

[wingnut60]

Gemstone...
Might not be any help to you, but, I ran into a similar situation--just about drove me crazy that the gas would not light, but electric worked fine-- checked everything and all seemed right. In my case, the water in the tank was too warm to let the burner fire!! I had been using the elec and just wanted to see if the gas worked. Gave up on it and turned the elec off--soon as it cooled down, on the burner came.
Maybe too simple and you aren't as dumb as me, but that's my story.
Joe

[Gemstone]

Thanks Joe...were you also getting a "DSI Fault" as indicated by the lighted switch in the control panel ? I'm guessing that a normal shower should dilute the hot water supply temperature enough to allow the LP burner to fire...I'll verify that this AM.

Regards
Gemstone

[wingnut60]

Yes, got the fault light. That is what threw me--made the assumption something was wrong. I think the fault light comes on every time you hit the switch, then goes out when it lights.
Probably something else with yours, just pointing out how little I know after owning this for 6 years...
Joe

[Gemstone]

Nope, after 2 showers, electric supply turned off, plenty of sparking, but still no LP being released, still showing a DSI fault. Guess we'll limp along on electric until we return to Yuma, where I have spare parts stashed. Will update in several weeks.

Thanks for the replies
Gemstone

[wingnut60]

Well, back to the gas valve...

[Gemstone]

Kinda my thoughts....I have a spare in Yuma, along with a control board.

Thanks for the input
Gemstone

[jas24]

The dealer's service dept. where I bought my MS, told me you have to have all the electric switches for the water heater turned off in order for the water heater to work on gas.

It's been so long....cannot remember if they were right or not.

[netjam]

jas24...Both my electric and gas will work at the same time.

[wingnut60]

Yes, mine will work with both at same time--makes for fast replacement of hot water.
Joe

[bstark]

The dealer's service dept. where I bought my MS, told me you have to have all the electric switches for the water heater turned off in order for the water heater to work on gas.

It's been so long....cannot remember if they were right or not.

Nope, nope; they will work in tandem. You can even have them both on together as in right after setting up with a cold tankfull.

You may have some crud in the valve pack that is preventing gas from getting past the solenoid valve into the burner tube.

Careful dissasembly and cleaning should be one of your troubleshooting exercises given that you say you can hear the solenoid lifting. My 05 had a dual pack coil with them wired in parallel I believe so you might have one coil functioning and the other not.

Unhooking the wires at the coil packs then verifying continuity across the spades should tell you if the packs are shot.

There may even be enough magnetic energy generated when the packs are active to be able to tell with a steel 6" scale held near to feel for attraction when they're energized.

It's been awhile since I've looked at one so my memory may not be the best on it.

[Gemstone]

Well, I finally got 'round to it, it was indeed the gas valve....I replaced the entire valve/burner unit with the spare I had stashed in Yuma, turned the gas on, checked for leaks, flipped the switch and it fired right up.

Regards
Gemstone