Troubleshooting Suburban Water heater not sparking to ignite

[howardwheeler]

I have the 10 gallon Suburban gas electric DSI hot water heater. Electric element is working fine, but I’ve lost gas ignition. I’ve cooled down the tank (to make sure it wasn’t just shut off at the thermostat) and still no spark sequence for gas ignition. Nothing happens on gas. The red light on the switch inside does light up but never goes out. Where would I begin to troubleshoot?

[howardwheeler]

Okay. If there was an interruption of propane flow, is there a lock out feature that would prevent it from doing anything for a few hours?

[BFL13]

Air in the gas line, cleared when you tried it many times? Refilled the propane tank lately? It could get air in the WH line but still be ok for the stove, eg.

[Ralph_Cramden]

howardwheeler wrote:
So the only way to tell is to access the board and take a look. I’ll have to recruit one of my more flexible grandkids to get up in the back of the storage bay to access the board. I think it’s time for a thorough tuneup on the hot water heater. I’ve got the anode rod to replace and am just going to go over the whole thing. Thanks

Unless you have access to or have an ignitor board tester, taking a look can sometimes tell you with a disclamer. They can also go toast and not show any burning. You can also test them out with a meter buts its a real PITA.

The last half dozen or so I have changed going back about a year and a half, have all had the part number / revision number in the last picture, and every one of those visibly fried.

[howardwheeler]

So the only way to tell is to access the board and take a look. I’ll have to recruit one of my more flexible grandkids to get up in the back of the storage bay to access the board. I think it’s time for a thorough tuneup on the hot water heater. I’ve got the anode rod to replace and am just going to go over the whole thing. Thanks

[Ralph_Cramden]

howardwheeler wrote:
Okay, good news and bad news. I went to the camper to try the thermostat reset, check the switch and clean the spark electrodes. I went inside to turn the switch on, turned it on and the red light came on as expected. As I always do, I then hurried outside to check the sparker. It was working!! Having done nothing, it started working!

When the ignitor board is trying to decide if its crapping the bed or not, that is what it sometimes does. It will work........then it will work intermittently, then eventually it will be toast.

I have replaced quite a few recently and every single one looked like this. They'll make it beyond warranty but then poof.

[howardwheeler]

I shut off the electric element and ran water until it was cold. Waited around ten minutes and then tried again. Nothing. Maybe it takes even longer for the thermostat to reset but when you’re using the hot water in normal conditions, the propane will come back on while the hot water is still running but the tank temp is dropping. So it seems I waited plenty long.

[BFL13]

You didn't cool the WH down enough the other day?

[howardwheeler]

Okay, good news and bad news. I went to the camper to try the thermostat reset, check the switch and clean the spark electrodes. I went inside to turn the switch on, turned it on and the red light came on as expected. As I always do, I then hurried outside to check the sparker. It was working!! Having done nothing, it started working! I'm supposed to be happy except now how do I troubleshoot it since it's working? Something went haywire. I tried to turn on and off the propane side of the heater multiple times over a couple of hours. Now the switch was off for two days and when turned back on it worked. Is there a shutout circuit that if it hasn't ignited over so many tries that it will stop trying for X hours? Maybe I caught it at the wrong time. It has every once in a while (very seldom) had the red light turn on and I have to turn it off then back on and everything goes back to normal. This time though nothing would happen no matter what I did.

[Jim-Linda]

Try this... remove the cover on the upper left side of the heater. There are two thermostats, left one is 120v, right one is 12v. There is a reset button(protruding) from the upper part, push this in and see if there is a click. If so the reset has tripped. Pushing on the rubber insert on the cover sometimes does not reset.

If no luck, where the burner tube goes into the chamber is the spark device. You will see a insulated wire going to a electrode. Carefully remove the electrode. Using fine sandpaper, polish both electrodes to remove any coating. Make sure the gap between the electrodes is <1/4 inch. Reassemble and try again. Caution.. when removing the black cover, there is a ridge around the edge that fits into the space where the 'stats are, use a screwdriver to gently get the cover loose around the entire edge....good luck

[howardwheeler]

When the switch is turned on there is complete silence—no spark no gas valve opening, nothing

[Travelin2]

The electrode, as you know, needs to be quite close to the burner. 3/16 inch or so. The burner itself needs to be well grounded for the spark to happen. Check with your multimeter to see that the burner is well grounded. If there is a lot of rust or loose connections, that could be the cause. If grounding is questionable you can route a ground wire there and see if the spark will jump to it.


Does the gas valve open and emit gass for a few seconds when you first turn it on? If so, then you should be able to light by match just to see if that part of the control board is functioning.

[Ralph_Cramden]

The OEM igniter boards are known to **** out and usually do so between the 2nd and 3rd year. If the board turns out to be the culprit forget about the OEM board and go HERE .

[pismopete]

I have the same water heater and had the same problem. I took some very fine sandpaper and polished the little rod that the spark jumps to and problem solved. Good luck.

[howardwheeler]

Thanks. Then I’ll try the switch first then the thermostats. I’ll try to get off easy. The control and junction boxes aren’t readily accessible.