Gas water heater will not ignite! (SOLVED)

[ACDC]

I’ve checked all what I can. Battery is good, propane tanks are full and ON, On off Switch is ON, water is in tank. Reset buttons checked. Fuses are good. Light switch comes on but indicator light does not and will not attemp to ignite. Not sure what to do next. Any suggestions?

 

[david-steph2018]

What is the make of the water heater? If Suburban there is another switch outside on the water heater itself. Stand outside next to it and have somebody try to light it off to see if you can hear the ignitor working. Does it do this on both electric and propane or just on one?

 

[danemayer]

Atwood or Suburban unit?

 

[ACDC]

It is a Sue urban unit on an Elkridge Heartland. I’ve tried to start with bbq lighter and no go as well. Turned off switch on tank and back on. No luck. 🤔

 

[cookie]

You mentioned turning your propane tank on, when you do that do it very slowly.
Also is the propane tank full? Does your stove work?

Pacer
Dave

 

[ACDC]

Yes double checked and turned on very slowly twice. Tried to start with bbq lighter as well and Tapped on thermocouple lightly.
checked wires for corrosion.

 

[danemayer]

On a Suburban water heater, the 12V DC/Propane operation is independent of the 120V AC operation. So assuming you have shore power, the 120V AC side should still work.

On the 12V DC/Propane operation, failure to attempt ignition is most likely 1) low or no DC voltage to the water heater. If your furnace works, it's probably not low voltage, but it could be a blown fuse in your main fuse box. If not a blown fuse, it could be a bad wire connection, most likely in the junction box on the inside front corner of the water heater. If there's also a failure on the 120V AC operation, the junction box is a prime suspect. If you can measure 12V DC at the 12V ECO/Thermostat (bottom terminal on the right hand side as shown below), it's probably a bad control board. A failure of the gas solenoid or electrode are low probability. If you have 12V DC at the top of right hand ECO/Thermostat assembly, but not at the bottom, that assembly has failed.

For 12V DC readings, the meter's ground probe must be on a known good ground.

 

[ACDC]

Thanks very much for your detailed explanation! That’s awesome. I will attempt looking at this tomorrow. Will update you afterwards. Thx again.

 

[JohnDar]

On a Suburban water heater, the 12V DC/Propane operation is independent of the 120V AC operation. So assuming you have shore power, the 120V AC side should still work.

On the 12V DC/Propane operation, failure to attempt ignition is most likely 1) low or no DC voltage to the water heater. If your furnace works, it's probably not low voltage, but it could be a blown fuse in your main fuse box. If not a blown fuse, it could be a bad wire connection, most likely in the junction box on the inside front corner of the water heater. If there's also a failure on the 120V AC operation, the junction box is a prime suspect. If you can measure 12V DC at the 12V ECO/Thermostat (bottom terminal on the right hand side as shown below), it's probably a bad control board. A failure of the gas solenoid or electrode are low probability. If you have 12V DC at the top of right hand ECO/Thermostat assembly, but not at the bottom, that assembly has failed.

For 12V DC readings, the meter's ground probe must be on a known good ground.
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Two other things to try. First, light a burner on the stove if the propane has been off for a while. That will get it flowing into the lines. When we were away from the rig for extended periods, we had to do that to get the water heater to light. Just turning on the valve at the tank didn't get it. Second, remove and clean the contacts on the valve body. Doesn't take much corrosion to block the current flow. Beyond that, there are the Hi-Limit switches, which can go bad. Used to be about $40 for a replacement. The other culprit is the circuit board on the back of the water heater tank. That runs about $80 or so.

 

[ACDC]

Problem Found!!! Reset emergency temp! Had to stick the prob inside the tube and voila we heard the reset click. This was after removing tank out from rv and checking all wires back from switch. This was found by mistake as it is not explained anywhere about sticking a fine wire or probe inside the reset button. All I had to do was remove round rubber plug off of reset button to reset. Would have been fixed in minutes vs hours. Thanks all for your excellent suggestions and hope this helps someone else down the road.
Cheers
Happy Camper!

 

[danemayer]

I think the reset button is supposed to operated by pressing on the rubber cover, which in turn pushes the button/tube. Sounds like something is misaligned with your reset. But yours might not be the only one like this, so your post will likely help others.