Water heater wiring diagram

[Rostam]

Hi folks,

I've bought an Atwood water heater and have a question about the wiring

The water heater came with its own switch. But, I already have a switch for the water heater in the control panel (in front of the trailer) that I'd like to use. So, I am not using the switch provided with the WH. I'd like to know how to do the wiring for the WH.

Attached please find the wiring diagram of the WH. It has 3 wires: green, brown, and blue. My Avion has also 3 wires coming out of the wall next to the water heater, but have different colors. I used a voltmeter and verified that one of them is a positive 12V and the other are negative (ground). The positive 12v is controlled by the WH switch on the control panel.

Looking at the attached wiring diagram, it seems I need to connect the positive 12 V to the brown wire and one of the ground wires to the green wire. My question is is it safe to connect the other ground wire to the blue wire? The only thing I see that is different is the Non-Ignition light is bypassed now (as the switch on the control panel does not have a light, unlike to switch provided by the WH). Is this going to cause a problem?

Thanks!

[Salty]

The three wires that were already in place one is +12VDC from the control panel switch, one is ground and the third is a return +12VDC that turns on the light in the control panel.
I believe the reasoning behind the +12VDC return is a troubleshooting measure - if the light is lit, you know there is 12VDC at the WH.
I don't know what the Current draw is on you WH, but those 16 gauge wires don't want to carry more than 5 amps.Well, I should say, you don't want those wires to carry more than 5 amps.
It would be useful to know if this WH is tankless, tanked, Gas only, gas and 120VAC etc ...

It is difficult to read your wiring diagram pic, as, when I magnify it, it just gets blurry. Maybe attach a better pic via PDF file?

[Rostam]

Salty,

Sorry, forgot to mention that. Its an Atwood G6A-8E, Direct Spark Ignition, 6 Gallon Water Heater. Dometic said its a direct replacement for Atwood G6A-2E, which was installed at the factory. I scanned the wiring digram page. But it seems the site shrinks the images after they are uploaded. I found a link to the manual though (The wiring diagram is on page 7):

https://www.gulfstreamcoach.com/media/u ... Manual.pdf

So, there are 3 wires coming out of the wall next to the water heater. I have figured out the 12V wire that is activated/deactivated by the water heater switch on the control panel. The other 2 wires are ground. Water heater has also 3 wires, although in different colors: brown, green, and blue.

Looking at the wiring diagram (The top one, 'Spark Ignition'), I know that the 12V wire must connect to brown wire. My question is does it matter which ground wire is connected to green and blue wires?

Many thanks!

[silverloaf]

Rostam-

Attached are the wire connections for my water heater. It is an Atwood on-demand unit. The wiring nearest to my hand come from the heater. The others go to either the control panel (blue and red) or ground (white).

In our trailer, all 12v positive interior wires are blue. Ground wires are either brown or white. The yellow wire to the control panel and red wire to the heater provide provide the feedback to the indicator light on the control panel.

[Rostam]

Thanks Silverloaf,

My water heater wires are green, brown, and blue. I wish there was some sort of standard there

Wires coming out of the trailer wall are white, yellow, and blue (similar to yours). However, using a volt meter, I have verified that the yellow wire is 12V. So, per wiring diagram, yellow wire should be connected to water heater's brown wire.

IF, white wire coming out of the wall is ground (on electrical panel, a thicker white wire goes to battery negative), then it should be connected to my water heater's green wire, and the third connection must be blue to blue and the puzzle is solved. My concern is what if white is NOT ground. What would happen? Could I fry something on the water heater if I'm wrong? I am sure white wire is not 12V (verified by volt meter that yellow wire is).

[Salty]

Please forgive me if I'm being Captain Obvious, but confirming the white is ground is easily done with an ohm meter. The ground on the three prong AC outlet is also DC ground. You could do that or check white to the frame, skin or worse case, the ground busbar behind the power panel.

[Rostam]

Salty,

This is why I always write down the problem description Many times, when you or others read it again, you find a solution to the problem.

So, I have already verified that yellow wire is 12V. I used my volt/ohm meter and there is zero resistance between the white wire and the ground on the three prong AC outlet. I did the same for the blue wire, and I got around 15 ohms. I think the blue wire is the return wire with the non-ignition light. I will attach the wires this weekend, unless the experts here have objections to my findings?

I must add, I really like the Avion community. Lots of knowledgeable, helpful folks. Thank you all.

[Salty]

Trailer Blue wire goes to the light in the control panel. Pretty sure.

So, for my money, trailer yellow and blue connect to WH brown. .
White trailer connects to WH green and Blue.

FYI, European standards use brown and blue for DC +/-.

[Rostam]

Salty,

That explains the color discrepancy as Dometic is (or was) a Swedish company.

BTW, I connected the wires this morning (WH Brown to trailer Yellow, WH Green to trailer White, WH Blue to trailer Blue), turned the water and LP on, and started the WH via the switch on control panel. It ignited and I had hot water shortly afterwards.

I must also say that Atwood customer support was not helpful. I called them every day last week and stayed on the line for 30 mins or more and they never picked up. I called them at 8:00 am on Friday and was the 1st in line and it took 1 hour and 20 mins for them to respond! They immediately said they cannot help and I should contact an electrician or my RV manufacturer. I told them I paid several hundred dollars for their product, was on hold for 80 minutes, and the least they can do is to answer a question about THEIR wiring diagram. The rep put me on hold, spoke with a technician, and said they cannot provide any other help besides whats in the diagram. I understand the liability aspect of this, and I don't expect them to help me with my Avion installation, but I think they should be able to tell me if someone swaps the blue and white wires on THEIR water heater to THEIR remote switch, whether thats going to cause a problem or not.Anyway, a lot of companies have terrible support these days and so this should not be surprising.

[silverloaf]

I went through the same crap-ola as you did with Dometic. I learned that, some time ago, they chose to drop tech support for retail customers. Instead, they only want to deal with aftermarket dealers or RV manufacturers.

After my last encounter with them, I swore never to put another Dometic product in our trailer.