New Water Heater Thermostat Failure

[mhs4771]

It sounds like it's time you called a Mobile Tech before you electrocute yourself or someone else.

[beeje]

Originally Posted by cgeis48

OK I understand better now. The two wires on the outside switch each have 120 V to ground.

Ok since you have 120 volts at both sides of the switch that means the switch is good.
Now take off the round black cover over the element. There should be a white and a black wire. Check voltage across the 2 wires. You should have 120 volts. If you do and the heater is indeed full of water than you have a bad element

[BB_TX]

Put your meter leads across the heating element terminals and see if you have 120 vac. If so and the water is not heating then the element is bad.

If you don’t read 120 vac across the heating element terminals, then move the neutral side meter lead to the metal case leaving the other lead on the element hot terminal. If you read 120 vac there but not across the two element terminals then you have a bad neutral. There have been several reports of a bad neutral wire connection in the junction box on the back or side of the water heater.

[beeje]

The OP needs to stay tuned. and report back so we all can help him out. Seams Elvis has left the building. LOL

[Daryles]

There is an inline fuse behind the control panel that goes to the electrical water heater switch.
Probably not a factor in this case but its there.

[Daryles]

one off the wall thing...
The black 15A furnace fuse somehow is connected to the water heater.
Discovered that by accident. Furnace kept cycling. Pulled the fuse to turn it off. Next day had no hot water. Remembered I pulled the furnace fuse the night before. Put the furnace fuse back in and the water heater started working.
Boy, I wish keystone would publish wiring diagrams...

[beeje]

Originally Posted by Daryles

There is an inline fuse behind the control panel that goes to the electrical water heater switch.
Probably not a factor in this case but its there.

I wonder if that's on all of them. If so never knew that was there. Probably there to protect the 12 volt circuit going to the relay at the water heater. You're probably right not a factor here since he has 120 volts at the switch

[cgeis48]

After spending most of a day tracing wires, checking valves, calling Suburban and Keystone and pulling out my hair, I called the lead tech at the dealership; he explained that the gas-fired hot water system failed to ignite because the tank water reached a preset temperature that was too warm to trigger the LPG heater. Therefore, we had no hot water even though the electric water heater was turned on (I cant explain). It seems the electric water heater was only able to keep the water at a lukewarm temperature which is just enough to keep the gas portion of the heater from firing up. If you want a clearer explanation - call your expert.

He told me to open the outside water heater drain valve long enough to cool the lukewarm water in the tank. I did that, and after a minute the gas heater fired up; again we finally had hot water. After we showered we turned off the gas heater and (for unknown reasons to me) the electric heating element is working again. I know this is strange and not explainable - if you know why please share.
So, if neither LPG nor 120V heats your water, with both turned ON, try opening the drain or running a faucet for and extended time. The cold water could do the trick. It workd for me.

[Daryles]

Oops, they mentioned that on page 11 of the manual

Troubleshooting LPG mode...
Note that if the water in the tank is already heated, the ignition sequence may not occur until the water cools to less than 100 degrees.

Happened to me too.

[beeje]

I know you can run it on the electric and LP at the same time to heat the water faster but I've never done that. If you're running it on LP or electric the temperature of the water shouldn't matter it should operate normally. If it needs to be heated it will heat it if it doesn't it will turn itself off. My recommendation is to use one or the other and refrain from running both at the same time

[rohrmann]

We regularly run our water heater with both modes. The recovery ratings of these units is with both modes operating and is how they are designed to be operated. When parked for a while we run electric. When dry camping, we run gas only. When shore power is available and more than one shower will be needed, we add the gas mode so the second shower doesn’t get cold.

[GreG L.]

What an education I knew knew I needed. Thanks all, this was a good read.

[beeje]

in my humble opinion that's why this and many other forums exists. We are all here to learn and help each other as best we can.

[GeorgeP.]

If you ran the water heater at anytime without water you may have toasted your heating element. You can also turn off water and power, drain water tank and remove heating element and check. It’s not a hard job but will take about an hour, also remove pressure from tank first and watch out for hot water.

[jimcol]

You don't have to remove element to check. Touch both leads with your Ohm meter. Should read something close to 12-16 ohms of resistance.

[BB_TX]

Originally Posted by jimcol

You don't have to remove element to check. Touch both leads with your Ohm meter. Should read something close to 12-16 ohms of resistance.

Just make sure power is off when you check resistance.

[rohrmann]

Also make sure at least one of the wires have been removed from the element so you get a true ohm reading.

[fftim29]

I have a 2016 3160RL. How does one get to the AC J-Box short of pulling the heater out the side wall? Any ideas appreciated!