Troubleshooting Suburban Water heater not sparking to ignite

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 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.

With mine it was the switch itself. You can take it out and by-pass the switch joining the wires to see if that works. Next in line after the switch is a small control board (plastic cover)

The switch does turn the red light on and off. Could it still be the switch? I’ll get out to the trailer and check. That sure would be the easiest to fix!

ISTR the light was separate as in this drawing, but it was in the 5er we had, so memory fading.

https://www.google.ca/search?q=suburban+rv+water+heater+parts+diagram&sa=X&biw=1024&bih=422&tbm=isch&source=iu&ictx=1&fir=V-LSdqIpY8ZFeM%253A%252CZB80fQSDAy1WzM%252C_&usg=AI4_-kQWBFXF2_wsuHCdYj8G6m3Gkt3ulA&ved=2ahUKEwjO1e2H-7bgAhVVLX0KHbWQD_kQ9QEwBXoECAYQDg#imgrc=V-LSdqIpY8ZFeM:

This wiring diagram does not show the electric heating element. Do you know if the same thermostat that seems first in line after the switch also controls the electric element? If so, I can assume the thermostat is not the problem since the electric element does come on.

There were two different thermostats, one for 120 and the other for 12v

There were two reset buttons on the outside under a black rubber cover, one for each ISTR.

My owner's manual (went with the 5er to new owner) had the schematics in it.

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.

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.

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 .