Water tank wire mystery

[ajriding]

Need help with wich wire is what.
I pulled this out of an RV.
Now I do not know which wire is positive. I know the green is neg bc it is grounded to the tank metal. There are two other colored wires, brown and blue.

I have the on/off switch. The colors do not match.
I had to cut the wires to remove both, and I assume somewhere in the middle, unseen, the wires changed colors.

I am selling this and have propane and DC to connect so I can demonstrate it, but I dont want to reverse the DC voltage. Or will it even hurt anything? I do not know what the third wire is, likely feedback to the switch that it is on.




The boiler switch is the upper left one, with a little circuit board behind it. White wire is grounded right there at the switch area (not the tank), then green and red wire come out. Red wire goes to the wirenut and to a bigger red wire. Green to green. But there is no red wire on the tank, and the green wire at the tank is grounded to the tank metal.
so blue and brown must connect to the switch. But which is which?

[Old-Biscuit]

ajriding wrote:
thanks guys, i didnt need a complete wiring schematic, I just needed to know the 3 wires that connect to the battery or switch.

I hooked it all up and the burner lit just fine.

And that info was provided.

[ajriding]

thanks guys, i didnt need a complete wiring schematic, I just needed to know the 3 wires that connect to the battery or switch.

I hooked it all up and the burner lit just fine.

[Old-Biscuit]

Wiring diagram

12VDC POS from battery goes to bottom terminal on switch
From Top terminal the 12VDC POS goes to Water Heater thermal fuse...to/thru T-stat and then to circuit board

Green is 12VDC NEG

Blue is for the Fault Light....12VDC POS comes from circuit board to Light if gas fails or ECO opens

[BFL13]

The wires on mine are-

Switch with red light inside: (Inside the rig, the on side is to your left looking at the red light) so on the back of that:

EDIT--with red light above the rocker switch!

on side, upper-Blue
on side , lower -White
off side, upper-green
off-side, lower-brown

Outside the plug to the circuit board has (not in order):
brown to left Tstat
brown to inside from right Tsat
blue to inside
red to eco right
(2 reds from eco left to gas valve)
green to frame and green from frame to inside

[ajriding]

Ranger Smith wrote:
Is it an Atwood . . . Here is wiring info

https://bestofwaterheater.blogspot.com/2019/06/atwood-water-heater-parts-g6a-7.html

Thanks. so both Brown and Blue are positive, Green negative?

Brown powers the valve, Blue powers the circuit board (which powers the piezo)? thats according the the link above.
Mine does not have two switches, it has one switch with 4 wires out of it.

If I put green on neg and both brown and Blue on positive will that be the way to run it ? I just need to run it for demonstration.

I really looking for an expert on this, not guesses.

-Out of the switch there is a thin pink wire that goes to a blue and white wire, so can I assume the blue/white goest to the blue?
I think pink is pos out.

-a thin gray wire that goes to a brown and white wire, so can assume goes to the brown wire?
I think gray is pos out.

- a thin black wire that goes to a red wire that goes back to the other switch labeled "test" and also has a yellow wires tied in that goes out to idk where...
I think black is pos in.

- a thin white wire that is ground.
it is ground for sure.

The wires are so thin I think they would be signal wires, not power-feed wires, though the valve and piezo prob do not need a lot of power... but they do connect to heavier gauge wires that would be sized for sending voltage as power.

The switch is also labeled "heater" which just illustrates how dumb RV design is. The heater is aka the furnace, which is all controlled with the thermostat, with no additional switches. The how water heater in this case is the "heater", or more clearly called a "boiler" though typically temps max out at 180 degrees, not 212.

[Ranger_Smith]

Is it an Atwood . . . Here is wiring info

https://bestofwaterheater.blogspot.com/2019/06/atwood-water-heater-parts-g6a-7.html

[ajriding]

Ranger Smith wrote:
One wire goes to the switch then the other side of the switch goes to +12 vdc. I believe the other wire is for the light on the switch when the propane does not fire up the red light comes on. Don't know which one is which.

I dont either, that is the whole point.

[Ranger_Smith]

One wire goes to the switch then the other side of the switch goes to +12 vdc. I believe the other wire is for the light on the switch when the propane does not fire up the red light comes on. Don't know which one is which.