broken water heater,wont fire

Thanks OB for describing the path.

westend wrote:
Try resetting the control board by pulling the fuse, tripping breaker, and having the switch in the "On" position. Have LED? No, check for 12V at the control board. Good idea to trip 120V breaker for gas troubleshooting.

You should have 12V through the control board, through the thermostat, through the limit switch, and to the gas valve. Igniter should fire if power is as above. If no spark, check igniter spacing and position.

Suburban 12V DC circuit and 120V AC circuit are completely independent systems. 12V DC only one that uses module board
Atwood uses a DC circuit board for both 120V AC and 12V DC functions (since 2004)

12V DC is fed from FUSED circuit in DC Dist Panel to the ON/OFF switch.
From switch to high t-stat/normal t-stat then to module board.
From module board to gas valve and ignitor at same time

No DC at On/Off switch....Main fuse
No DC at high t-stat...bad switch
No DC at normal t-stat ....bad t-stat set (burnt connector wire) OR high t-stat needs RESET
(Remove rubber cover to test 12V DC...red wires/gas and check if high to normal t-stat wire is burnt)

Try resetting the control board by pulling the fuse, tripping breaker, and having the switch in the "On" position. Have LED? No, check for 12V at the control board. Good idea to trip 120V breaker for gas troubleshooting.

You should have 12V through the control board, through the thermostat, through the limit switch, and to the gas valve. Igniter should fire if power is as above. If no spark, check igniter spacing and position.

I did the same thing early in this camping season. After blowing lines for winterizing (I usually run the pink stuff), I forgot the by-pass was on. When filling up with water, water came out the faucet just fine! It sputtered and I though all the air was out. Nope! Long story short...

I fired it up on electric first. Burned up the electric heating element.

Still didn't realize there was no water in the tank and flipped on gas.

It fired, I though everything was ok. Later tried the water ... cold (still on bypass)... Then it hit me. OH ****!

Well, the gas would not fire and electric was dead..

Long story short, took it to my dealer for repair. Replaced the electric heating element and the thermostat! yup, I destroyed the thermostat!

Got it fixed and everything has been fine since.

Old-Biscuit wrote:
Suburban does NOT use the 'thermal fuse' like Atwood


You dry fired it........hopefully you did NOT put cold water in it until AFTER tank cooled down!

Check the high temp t-stat 'reset'
In outside compartment is PUSH TO RESET button above gas valve.
Good chance it tripped.

Only other thing would be a blown main fuse in DC DIST Panel for the water heater






WAIT A MINUTE:
This 'dry fire' issue is SAME thing back in Sept of 2015
Did you dry fire AGAIN....or did you just ignore the responses from 9/7/15

Last years post ----SAME issue!

:S

no not the same issue figured that out .this is something else.

Suburban does NOT use the 'thermal fuse' like Atwood


You dry fired it........hopefully you did NOT put cold water in it until AFTER tank cooled down!

Check the high temp t-stat 'reset'
In outside compartment is PUSH TO RESET button above gas valve.
Good chance it tripped.

Only other thing would be a blown main fuse in DC DIST Panel for the water heater






WAIT A MINUTE:
This 'dry fire' issue is SAME thing back in Sept of 2015
Did you dry fire AGAIN....or did you just ignore the responses from 9/7/15

Last years post ----SAME issue!

:S

Check for voltage at the water heater. There is thermal fuses under the heat shrink type tubing adjacent to the ECO and thermostat in the brown wire.

Check the fuses, I hope the tank is ok if you fired it dry could be other problems..

2oldman wrote:
any water in it? I see you've also posted this in tech. You sure seem to have problems with water heaters!

no .I forgot to turn the valves.it fired on a dry tank.as I said the led on the control panel wont come on after you push the on switch.

any water in it? I see you've also posted this in tech. You sure seem to have problems with water heaters!