Wednesday, May 10, 2017

Atwood RV Gas/Electric Combo Water Heater

The external side of the Atwood RV Gas/Electric Combo Water Heater.

Lots of info at:

What is not discussed clearly in the paperwork is there is no real connection between the gas side and the electric side of the Atwood RV Gas/Electric Combo Water Heater. If you lose water on the electric side, you do not need to waste time on the gas side... they do not interconnect. If your gas problem is anything besides changing the E.C.O. and T'stat, you need to see a certified propane gas technician.

Technical info that applies to the water heater. This information is mounted on the right vertical inside the RV water heater access.

Replacement E.C.O. (Emergency Cut Off) and T'Stat (Thermostat) for the gas side of the water heater.  The you tube video at: explains how to replace the gas side ECO and T'Stat. Both twist under tabs in the sheet metal frame of the water heater. On mine someone previos had pounded the tabs flat. DO NOT POUND TABS FLAT!!!!!!!

The electric E.C.O. and T'Stat are very similar but different as they are 110 volts and the gas side is 12 volts.

The access cover for the electric side of the water heater. In my RV this is located under the bedroom cupboard. To gain access you must remove two large drawers and work through the drawer access.

What I found upon opening the electrical access cover.

A larger view. Obviously this has been worked before because there are three types of wire, including twisted wire that is burned up. I think a wire nut came loose and the resulting short burned up the wiring.

The jumper wire between the E.C.O. (Emergency Cut Off) and the T'stat (Thermostat) is also charred. This picture shows how the ECO and T'stat are mounted on the electric side. The galvanized plate is removed, and both units are put under the plate and the plate removed. I used all pieces of each in the install.

My rig uses a Romex 14-2 cable to provide power to the electric side of the hot water heater. In mine, the excess cable is firmly stuck under the water heater. Therefore, I had to install a metal junction box in order to have enough Romex to reconnect the water heater.

This piece of gasket also burned uo, it was over the ECO and T'stat, I found a roll of rubber gasket material that is closely matched at a local auto parts store and cut out a replacement.

This picture was taken from a you tube video at:
It is very informative, but I used this picture of the electric side to ensure all my wiring was correct.

The electric heating element measures 10 ohms of resistance if it is good. Mine did not need replacement.

I purchased a 15 foot section of 14-2 Romex and used that to extend my wire through a junction box. I also cut and stripped the cable as required to make the jumper and connecting wires that I needed. The ECO and T'stat require the use of insulated Flag connectors as the wire comes off the terminals at 90 degrees. I also used heat shrink on my ground cable inside the access panel to prevent anything shorting inside the box. Make sure wire nuts are tight to prevent them from coming off. 

Take special care when reattaching the access cover as the area you are working in is very tight.

The view form the drawer access, with everything closed up.

The view from RV bedroom.