No 12 volt power/ Auto Breaker click

[AlexGO]

This is our first RV trailer, it's a 2018 Forest River T28CKDS. The start of our problems began when my sister and mother decided to fire up the water heater for the first time in owing this RV. Then suddenly the RV lost all 12 volt power no lights, etc. We have replaced the Converter and that wasn't the issue, Installed a new Auto reset breaker because the other had burned out, and today new batteries. What I've noticed is that when I connect the batteries the Auto Reset breaker will just click over and over. Is this a short? or I've read that maybe upgrading to a 50 amp can fix this. Can someone please help.

[5picker]

Welcome to the forum, I see it is your 1st post.

Sorry you are having issues.
Yes, a clicking auto-reset circuit breaker is an indication of a short.
DO NOT replace with a higher amperage breaker until you do some testing of the circuits.

Do you own a multimeter and know how to test basic electrical circuits?
It seems you've been throwing parts (converter, battery, breaker) at trying to fix this instead of performing the proper diagnostics.

What make/model water heater do you have?
Is it both LP (propane) and 120v?
If both, when you tried to use the water heater were you turning on the LP side of the WH or the 120v side?

[SeaDog]

Welcome to the forum its a great place to get your questions answered. X2 what 5picker said, I think if it started with the water heater I would start there with my trouble shooting. good luck let the forum know what you find along with the info 5picker requested.

[Tabasco_Joe]

Open the door to the electrical panel and find the maker/model of your panel.
Go to that maker's WEB site and get a manual for that model panel.
It will help immensely in troubleshooting.

[AlexGO]

Yes the heater is both propane and electrical, i have used the multimeter to get readings and such. I believe my mom had been running it on propane during the time. As someone mentioned to check at the heater because it was what might of caused the issue. I have opened the heater panel and the RESET breaker wont reset. Its almost as if its locked in position. Could this be my issue?

[AlexGO]

I've read that when the water heater heats up to much it can blow a Thermal fuse and make the RV lose all 12 volt power could this be the issue?
"Thermal Fuse (Clear tubing) connected to t-stat is a 'one time temp fuse'. IF it blows it has to be replaced. When it blows ALL 12V DC power is lost.....nothing will work until replaced.
It is a safety device that burns out at 190*F .....it is for flame blow-back out of combustion chamber/burner tube.

[mnoland30]

Did the water heater have water in it when they turned it on? If the bypass valves were open, it might not have, and that would burn up the element. It is possible that could cause a direct short. I'd pull the electric heating element to check it.

[Larry-NC]

Originally Posted by mnoland30

Did the water heater have water in it when they turned it on? If the bypass valves were open, it might not have, and that would burn up the element. It is possible that could cause a direct short. I'd pull the electric heating element to check it.

You don't need to pull the element to check it. Just turn off power, disconnect one lead from element, and measure the resistance between the two terminals. You need to be on the lowest Ohms scale. A good element has 12-13 ohms resistance. A shorted one would have substantially lower resistance.

Also check the resistance from each terminal to ground (any water heater fitting), as one element failure mode is where the nichrome heating coil comes in contact with the steel case.

A heater element that failed as a short would definitely trip the water heater 20 amp breaker in the power panel. And the OP wouldn't be able to reset it. A quick test would be to turn off the 120 Vac at the heater (hidden switch accessible from the outside panel at the lower left). If that switch were turned off, the OP should be able to reset the circuit breaker.

But I'm confused. The other symptoms (frozen thermostat or limit switch, auto-reset breaker tripping) point to 12 Vdc issues.

I think there are two different things going on here.

[5picker]

Originally Posted by Larry-NC

You don't need to pull the element to check it. Just turn off power, disconnect one lead from element, and measure the resistance between the two terminals. You need to be on the lowest Ohms scale. A good element has 12-13 ohms resistance. A shorted one would have substantially lower resistance.



Also check the resistance from each terminal to ground (any water heater fitting), as one element failure mode is where the nichrome heating coil comes in contact with the steel case.



A heater element that failed as a short would definitely trip the water heater 20 amp breaker in the power panel. And the OP wouldn't be able to reset it. A quick test would be to turn off the 120 Vac at the heater (hidden switch accessible from the outside panel at the lower left). If that switch were turned off, the OP should be able to reset the circuit breaker.



But I'm confused. The other symptoms (frozen thermostat or limit switch, auto-reset breaker tripping) point to 12 Vdc issues.



I think there are two different things going on here.

Great information Larry and I agree, I think the OP has other 12v DC issues and believe they are confusing what they read about the thermal fuse cutting off all 12v power. That would only be, all 12v power to the water heater, not the entire R/V.

[Tom48]

How about completely disconnecting the water heater from the 12 volt electric and see if that solves your problem before you go deep diving in the water heater