Water Heater Problem

Cracker · 06-08-2004, 08:26 AM

I posted a question last night but it apparently disappeared into the ether!

My WH works great on propane. It lights up right away and heats relatively fast. The problem is with the electrical heating element and related circuit. I contacted Atwood and they sent me a trouble-shooting guide. The problem is that I can't get to the trailer right away and Atwood's guide has me scratching my head trying to figure out what's what. Is the ECO high limit switch Atwood refers to the same switch otherwise known as a "re-set button" - and as located inside the junction box cover (on the bathroom side of the heater) with the rocker switch mounted on it (accessible by using the eraser end of a pencil) - or is it yet another switch located on the external side of the heater? When I did an earlier search, someone had submitted a photograph that showed the ECO switch on the external side of the heater. The photo looks like my heater but when I was "wiggling" all of the wire connections on the heater I didn't notice a switch where indicated in the photo??? This may become more obvious to me when I can get to the trailer - but if anyone has a simple explanation I would sure appreciate it.

thenewkid64 · 06-08-2004, 10:06 AM

My understanding is that once the ECO is tripper on the electric side it must be replaced. It is a one time use Electric Cut Off. IF it has a reset I could not find it on the WH I installed in my 76 MH. All it said was that if the ECO pops you need to replace it. The ECO normally pops due to an unsafe temperature in the tank so it is normally mounted to the tank itself.

Cracker · 06-08-2004, 02:55 PM

Brett G:

According to Attwood's trouble-shooting sheet the ECO switch is a "manual" re-set. I'll know more about it tonight.

Cracker · 06-11-2004, 07:42 AM

Just as a follow-up, and in case anyone else is having a similar problem, I was successful in getting the electrical side of my WH back in operation. When I removed the access cover on the inside face of the heater (--- the box/cover with the toggle switch on it) I was surprised to find that the entire electrical heating element apparatus, including the ECO, the thermostat, and the element itself, was located under this cover. Apparently the 120 volt electrical side of the heater has no relationship whatsoever to the propane side. With both switches on (---the wall switch as well as the toggle switch on the box) there was no power at the heating element connections - although I had power up to the box from the wall switch. The ECO is a tiny unit with the "reset" button located between the spade connectors (---that wasn't obvious looking through the "pencil hole" provided in the cover.) I turned off both switches and, after depressing the ECO "reset" button several times - with no "audible" response - I ran a continuity check across the spade terminals and got positive results. I then ran the same continuity check on the thermostat (---which looks just like the ECO) and the heating element itself - and I got positive results on both of those units. From there I ran a complete continuity check on the wiring harness, up to the toggle switch on the box, and that too gave a positive result. At that point I turned both of the switches back on and checked the terminals of the element. Hooray - I got a good 120 volt reading! Now I'm not sure if I had a corrosion problem - or if the ECO reset switch was not re-engaged. For the record, I had completely removed the ECO switch from the mounting plate when I was checking the reset button. Surprisingly, when I depressed the button against an apparent spring resistance I lost continuity, but, when I released it, continuity was restored. That seems sort of backward to me but regardless, when I checked this morning I had plenty of hot water!