Water heater won’t light

[jsm5394]

Hello,
The T-2499 I recently bought had been stored for three years, indoors. All works well except for the water heater. It’s a GC6AA-9-E. It has power, water and LP. I turn it on via the control panel and I can hear the spark firing. I can’t hear or see gas however at the burner. Any ideas?
Jim M

[JohnB]

Hi Jim,

The water heater has both clicks and clunks to it that can tell a lot about what is and is not working.

With a helper inside the camper, go outside and let the white cover down on the water heater.

While watching and listening outside, have the person inside flip on the red rocker switch at the tank panel for LP gas operation on the heater.

Within a few seconds wait, you should hear, click, click click of the spark ignitor going off. As soon as it starts clicking, you should hear one good "clunk" of the gas valve opening. No clunk, no gas valve opening.

The system has a self check circuit that it tries to fire the water heater 3 times, it if fails to fire off, it will shut down the system on safety and turn on a tiny red light on the tank panel inside what says in tiny letters, DSI fault. (DSI = Direct Spark Ignition) That tiny light in in-between the red rocker systems. You can miss it if you are not looking for it.

The system will turn on the igniter for several seconds and then shut off to let any gas clear for several more seconds. You should hear the same one large clunk, when the gas vale closes. After a time period, a trail for ignition will start again, one gas valve clunk, click click click and then time out. Again a clunk when the gas valve closes. After the 3rd try, the system locks out on safety.

To reset the system, turn off the LP gas red rocker switch inside, that resets the fault and you can try again and get 3 more tries.

See if you can hear the gas valve opening. If it does open, then the question is, is if getting any gas?

I know on my T2499, it often took 2 times of DSI faults to get the heater to fire off on gas to get the air out of the lines. The heater is all the way in the back of the camper. It is the last in line. Make sure the stove burners light then try the water heater. You can also cycle the furnace which is a big gas user, air purger, and when it fires, gas is real close to the water heater.

Try the above and let us know how it goes. We can dig deeper into this once you can verify you can hear the clicks and clunks happening.

Hope this helps

John

[jsm5394]

I hear a soft clunk just before the electronic ignition fires, not after. The furnace, stove and fridge have gas and work fine. On the water heater I can’t hear any gas flowing nor can I smell gas.

[JohnB]

Originally Posted by jsm5394

I hear a soft clunk just before the electronic ignition fires, not after. The furnace, stove and fridge have gas and work fine. On the water heater I can’t hear any gas flowing nor can I smell gas.

Hi Jim,

The timing of when the gas valve clunks and the start of clicks of the igniters is almost the same. If you heard the faint clunk (some are louder then others) but you still heard the gas valve being powered up, and the igniter was clicking, that is a good sign the control system is working.

Now, with the furnace able to fire off, and you cannot smell any gas at all, well you may have other issues, but we now know the controls are working.

When was the last time this water heater was run on LP gas?

It is possible insects have clogged the burner tube. This is semi common. Sometimes it is just spiders making nests, other times stink bugs crawl in and die, lots of them, and other times the worst, mud daubers move in and they make a real big mess. Use a flash light and look real close in the gas burner, the air shutter slots for any blockage. You may have to take the gas burner off to inspect it close enough. You do not have to take the gas valve off, it can stay in place if needed. The bracket that holds the gas valve and burner does need to come off, but the gas valve can stay attached to the copper feed line. Take care around the igniter porcelain to not crack it. Make sure the 12 volt power is off and the LP gas.

The gas valve has a brass nozzle on the end of it and a tiny gas orifce jet screwed in the end of the larger brass nozzle. If that orifce is plugged, no gas will come out, and the main burner tube being plugged is an issue too. You can unscrew the orifce tip from the larger brass nozzle while the nozzle is still in the gas valve. Just hold the nozzle with a wrench while taking the orifce tip out.

Do not pin stick or anything else in that gas orifice. You can unscrew the tip and soak it in alcohol and then look through it with a light. The human eye can see through that hole. That will tell if it is open or clogged.

The main gas burner is easy to see and once removed from the heater, you can clean it out with a wire or small round wire brush. The burner is a big hole. There is also an Air shutter on the burner tube, a screw holds it from sliding. Make sure you mark where it is so it goes back to that area.

This link will take to a water heater, same vintage as yours, total rebuild. It has lots of pics which may help https://www.sunlineclub.com/forums/f...tml#post154839

Let us know what you find and if you need more help

John

PS, do not blow compressed air back towards the gas valve. It may plug dirt into that gas valve orifce. Blow down stream of the orifce if needed.

If anything I mentioned above is beyond your means, let it be and find a gas stove or RV repair guy. We are not sure of your abilities.