Water Heater Blowing Thermal Cut Off Fuse

[cwhite6]

I have a 2021 Imagine 2800BH. We are using it right now on our second trip since getting it. I am having an issue with the water heater blowing the thermal cut off fuse. Heater was working just fine. We turned on the gas and electric at the same time to all take showers (4 of us). After the second person finished, we gave it about 20 minutes to heat back up and had no hot water. After troubleshooting, I discovered the thermal cut off fuse was blown. I bypassed it to finish showers (only running the propane heater) and then shut the heater off for the night. I went to the local RV parts place and bought another fuse and replaced it. Ran fine again and then blew again later that evening.

I was under the impression I could run the electric and propane heaters together for as long as I wanted. Is there a time limit I don't know about? The weather is here is mid 80's, so we are running the AC also.

[Jlawles2]

Found this in a quick search to see what exactly a thermal cut off fuse was:

https://www.rv.net/forum/index.cfm/f...d/16316671.cfm

Guess it's generating too much heat in the compartment.

[howson]

I have a 2021 Imagine 2800BH. We are using it right now on our second trip since getting it. I am having an issue with the water heater blowing the thermal cut off fuse. Heater was working just fine. We turned on the gas and electric at the same time to all take showers (4 of us). After the second person finished, we gave it about 20 minutes to heat back up and had no hot water. After troubleshooting, I discovered the thermal cut off fuse was blown. I bypassed it to finish showers (only running the propane heater) and then shut the heater off for the night. I went to the local RV parts place and bought another fuse and replaced it. Ran fine again and then blew again later that evening.

I was under the impression I could run the electric and propane heaters together for as long as I wanted. Is there a time limit I don't know about? The weather is here is mid 80's, so we are running the AC also.

First--welcome to the forum. Check out the Welcome Letter to New Members at https://gdrvowners.com/forum/main-fo...to-new-members

I don't have my notes with me at work, but if I remember correctly the thermal cut-off fuse is a safety device if the fixed thermostat fails to operate (heater doesn't turn off when it reaches temperature). If the fuse is blowing it's doing it's job. I suspect what you're finding is the symptom, not the problem.

Find the fixed temp thermostat on the heater circuit. My .02 is on that part being bad.

Howard

P.S. Please don't take offense, but until you're sure of the problem bypassing the temp fuse is not safe IMHO--that's like putting a paper clip across an electrical fuse to power a circuit. Not a good idea to bypass a safety device.

[Jimmer]

I just picked up a 2021 Reflection Travel Trailer. For my water heater, the fault light kept coming on during the maiden voyage. The light means that the gas flame is not igniting, or that the water heater is overheating. After investigating, I found that the thermostat was not secured, and therefore not pressing against the tank. Thus, the water heater kept heating until an overheat condition was detected by the ECO (don't know what that stands for).

Look at the attached picture. If your water heater is the same, wiggle the wires that are plugged into T'STAT portion. if it feels like they are loose, maybe your thermostat is not properly mounted against the tank, like mine. I disconnected the wires to the T'STAT, lifted the foam covering, resecured the thermostat, and it has worked perfectly since then. Let us know if your thermostat is loose.

[Country Campers]

I have seen loose connections cause this problem before , as mentioned above by Jimmer . Check all of the connections before you start purchasing items.

Brian

[cwhite6]

Thanks for all the info folks. I will look at the thermostat as suggested. As far as by passing, the camp ground we are at has all of the bath houses closed. The three ladies in the camper with me were not going to take cold showers. What’s weird, it never does this when using the electric or gas only. Only with both and only if both are on for a while. I hope it is an easy fix like y’all suggested. This thing is brand new and it already spent a month getting the fridge fixed that never worked right.

[howson]

What’s weird, it never does this when using the electric or gas only. Only with both and only if both are on for a while

The thermostat may still be operational but doesn't react fast enough due to how quickly the water is heated with both gas and electric. Not unknown given how a thermistor works (the core component to the "thermostat" device on the water heater).

I've heated the water in my tank numerous times using both gas and electric, so there's nothing wrong with turning them both on. Until you can figure out the issue, the ladies will just have to be patient while the water heats up a little slower using only one source (with the safety thermo-fuse installed).

[cwhite6]

That’s what we are doing now. Only gas during showers. I turn the gas off and use the electric for dishes and such. I am going to check the heater out after dinner and install another thermostat fuse from the pack I bought. If it doesn’t resolve, I will bring it back to the dealer again when we get home.

[howson]

cwhite6 -- would appreciate a follow-up with the fix once you get it resolved. That's the power of an owners' forum--the sharing of information.

[cwhite6]

I went outside and changed the cut off with a new one. I also checked all the wires and everything is tight. My thermostat is on a spring where it holds it in place and it is tight and installed right. We will see what happens. We are just going to use the gas heater only for showers and electric for other stuff.

[Jlawles2]

Save the testing for the last day when you are leaving just in case something else happens.

By chance are any of you leaving the shower on the whole time? I know both of us turn the shower off at the head with the slider when soaping up or washing our hair. Long Hair and lots of rinsing do not help hot water situations.

One other thing you may try is to give the HWH a break between showers. It does not take long, but some time for the burner heat to dissipate that builds up inside the control area of the HWH. Also look around to see if there are any gaps in the burner discharge flue that will allow excess heat into the control area. Might even try foil tape to help direct the heat from the fuse.

[Country Campers]

We have used ours in the gas mode , electric , and gas/electric. The best for recovery while using hot water is the gas. I have not found the gas/electric mode to make any difference in recovery while using , not even sure if it makes a difference when just heating up the first time. We use electric , when available , to keep the water hot and dishes and such but when showering have found that just gas does a good enough job. We also turn off water while soaping.

Brian

[cwhite6]

They are learning how to Ranger shower!! We are heading home today and camper is going to the dealer. We were in the Orange Beach area when that hail storm came through. Lots of damaged campers and shattered windshields. Pretty much everything on top of my camper is either shattered or gone along with other damage. I will let the dealer look at the water heater also.

[howson]

They are learning how to Ranger shower!! We are heading home today and camper is going to the dealer. We were in the Orange Beach area when that hail storm came through. Lots of damaged campers and shattered windshields. Pretty much everything on top of my camper is either shattered or gone along with other damage. I will let the dealer look at the water heater also.

Bummer. Yep, that storm blew through here this morning and branches were flying everywhere. Sorry to read about the damage to your camper. :(

I've got to get out and inspect my roof...

[cwhite6]

Camper has $14k in damage including a new roof for the camper and slide. It is in the process of being fixed and should be done in a few weeks.