Hot Water heater not working

[Carl n Susan]

cait4290: The best approach is to grab you VOM and download the Suburban Heater Diagnostic manual from our Files Section https://www.montanaowners.com/forums...?do=file&id=90 and jump in.
I am assuming , from what you wrote, it is the electric side that is not working. That is good as if the propane side works, it likely eliminates the control board.

[Daryles]

The Suburban Water heater manual is in the files section.
I looked at the wiring diagram but I didn't see where the reset switches are in the circuit.
I would take the rubber cover off the reset switches and check for voltage on each side.

[rohrmann]

Originally Posted by laverdur

I read enough of this thread to know it your electric side that is not working. Same thing happened to me when my Monty was fairly new. Al little troubleshooting with a multi-meter revealed the problem was a failed thermostat on the water heater. It was a 5 minute fix after I drove across three states to find a replacement thermostat.

I’ll bet the plastic reset button on the thermostat that failed was red in color. Ours failed early on and I was able to locate a replacement local to where we were staying. Turns out that the vendor that made those thermostats did not make them quite to specs for Suburban that year and most were failing. I guess there was a recall so Suburban should have paid for my replacement, but didn’t find out about that until a couple years later.

[rohrmann]

Originally Posted by beeje

Had the same exact issue last year, except much worse looking. I eliminated the 12 volt relay and installed a 120 volt switch in the wall of the bathroom to control the heater.

By the way, your title says ("Hot water heater"). A George Carlon original, You don't need to heat hot water. LOL

I think we should start calling them Cold water heaters, just to be different. 😜

[Carl n Susan]

Bob: those faulty thermostats with the red reset button was a 2012 to 2014 feature. The OP has a 2021 which should have the improved grey button.

As Daryles suggested, popping the plastic cover will give you direct access to the thermostat. There should be 120V on both sides of the thermostat when it is heating (the thermostat doesn't allow heat until the water temp drops to around 110 degrees). If voltage is not present on the input (lower) side, then the most common cause if the rocker switch in the lower left corner. The 2021 should have the rocker although it was eliminated in 2023 or so.

[rohrmann]

I was replying to laverdur, who has a 2012 rig.

[cait42190]

Thank you for the help/reply. We are new fifth wheel owners and made a bone head move by not turning on the hot heater switch inside the rv. We had hot water within minutes.

[BB_TX]

Yeah, none of the rest of us, even us old timers, ever make “bonehead” mistakes.

[Pippin]

I am 61 yrs old and cannot recall one incident in my life in which 120 volts killed. Not saying it doesn't happen. But I would bet $1000 that 99% of people also cannot recall one incident. And yet pretty well everyone, by mid-life, must have felt 120V at some time in their life. "High-voltage current (greater than 500 V to 1000 V) typically will result in deep burns, while low-voltage current (110 V to 120 V) is more likely to result in tetany" (https://www.ncbi.nlm.nih.gov/books/NBK448087/.

[LeftOverParts]

Does the heater work when on elect or propane?

In general, turn off the circuit breaker to the water heater and remove the rubber cover to access the thermostats. One is for propane, the other is for elect. You can check if anything is visually wrong - over heated (bowed out/stiff reset), loose wire, shorted wire, etc.

Tell us what you find. Post a picture if you think it will help.

If they look OK, a volt meter can be used to check power at the stats and then at the heating element.