Community Forums

mcentirejerr · 08-12-2019, 07:20 PM

My hot water heater quit on ac, I discovered there is no power at the ac outlet, so checked the breaker and it’s working fine. There is power from the breaker to the EMS control board but I’m lost after that. Does anyone know where the wires are from the board to the heater outlet? I really don’t want to have to pull walls to find the wires.
Pics of breaker box and control board attached

jacwjames · 08-12-2019, 07:41 PM

What year is your Diplomat? Do you have a wiring schematic for the coach?

Do you have a separate switch that turns the water heater off/on? If so could be a couple of possibilities.

My ON/Off switch quite working, when I looked at the wiring circuit there was a 12 volt fuse for the switch, I finally found it mounted in the kitchen base cabinet behind where the switch is located.

On my coach I have a separate switch for the water heater. The switch is 12 volt and goes to a relay that sends power to the water heater. The relay is mounted in a small 6X6" Ormin electrical box mounted behind the main breaker panel. Tis is shown on the wiring diagram for my coach. Hard to get to. There is another relay in the same box that controls the engine heat relay.

450Donn · 08-12-2019, 08:05 PM

If it just quit, I would start at the switch, take it apart and loom. RV manufacturers tend to use the cheapest crap possible. Push on connectors are the norm. And they tend to go loose and fail.

mcentirejerr · 08-12-2019, 10:56 PM

2001

mcentirejerr · 08-12-2019, 10:59 PM

Thank all of you for your responses I will continue troubleshooting tomorrow. Knowing it has a dc relay helps.

veraken · 08-13-2019, 05:42 AM

Here are the wiring diagrams for a 2000 Diplomat which may help you.

jacwjames · 08-13-2019, 07:34 AM

The 2000 Diplomat wiring diagram does not show an EMS.

Do you know what make/model water heater you have?

mcentirejerr · 08-13-2019, 09:29 AM

Quote:

Originally Posted by jacwjames

The 2000 Diplomat wiring diagram does not show an EMS.

Do you know what make/model water heater you have?

I’m guessing it was a upgrade
It’s a Atwood heater, I can’t find anything wrong with it. There’s just no AC power at receptical.

mcentirejerr · 08-13-2019, 09:33 AM

Checked the on of switch and everything there is AC kinda like a household light switch.

l1v3fr33ord1 · 08-13-2019, 11:36 AM

mcentirejerr-

You may find this post

http://www.irv2.com/forums/f115/wiri...ml#post4112681

and this thread (by "jacwjames/Jim J")

http://www.irv2.com/forums/f115/2002...em-228158.html

helpful. On the other hand, none of it may apply to your coach.

You should add a "signature" to your profile. It contains whatever info you want; most people put info about their coach there, so they don't have to type it into each message. Instructions for adding a signature are here.

mcentirejerr · 08-14-2019, 06:34 PM

Finally figured it out, there is nothing but wiring behind both breaker boxes. The relays are part of the circuit board in the picture I posted. After testing and figuring out which wires went to what I bypassed the relay by connecting the 2 wires together and have power again. Of course that means my heater want be on the EMS until I replace the board.
As usual what I own has to be different than what’s normal. Thank all of you for trying to help

jacwjames · 08-16-2019, 06:53 PM

If your board is bad and you can't find a direct replacement (obsolete when I had to change mine in 2014) you will have to upgrade. Not difficult but you will need a new wiring harness and load meter. When I contacted M&M they sold me what I needed. Cost was ~$450 at the time.
If you check other sources make sure you get the complete upgrade kit, when I was checking most didn't offer all the parts. That's why ended up going with M&M, great to work with.

Happycarz · 08-18-2019, 09:35 PM

Years ago, one of our electrical engineer types replaced the faulty relay on the board. He purchased them from Mouser.com. I figured if I kept the part numbers on file, mine would never fail. I still have my fingers crossed!

The part numbers are:

653-G8P1A4PVDDC12OZ

653-G5LE-14-DC12

I hope this helps and you can save some money. Let us know how it works out.