Water Heater Question

Bulldog48

Senior Member
Joined
Oct 13, 2018
Posts
116
Have 2011 3400RL. Not getting electric to Suburban water heater. Juice at in side breaker and inside on off switch. Replaced outside switch, thermostat and heating element. Is there another fuse somewhere? Does the circuit board get juice before out side on/off switch.
 
Your inside switch on the panel is only 12 volts that controls a relay mounted on the outside of the water heater. It's possible that there is a problem with that relay or the wiring at the relay. You will probably have to pull the water heater out at least part way to access the relay.
 
That relay is in a junction box on the side of the water heater. Someone posted a picture of it some time ago, but I have no idea now who that was or how to find it.

I also added a number of other comments on your same question in the Facebook Montana group.

Edit: I believe it is the small metal box at the top left behind the front flange.
 

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The Suburban Water heater service manual is in the files section.
As mentioned above, the relay is in the box on the side. Depending on your rig, you have to pull the water heater out a bit to get to it.
The inside control panel "WH Electric" switch turns on 12vdc relay which allows 120vac to the element.
You can check for 120vac at the element.
Turn OFF electricity, disconnect the black (hot) and white (neutral) wire. Check ohms across the element terminals. Should be about 8 to 10 ohms.
Also read white (neutral) wire to ground (frame). Should be 0 ohms.
 

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Bill your picture put me in the right area. I have a metal junction box where the one in the picture shows relay. And the relay is inside the junction box and is about the 1/3 as big as the one in the picture. I lucked out and didn't have to remove the heater, I could get to it through the kitchen cabinet. Tight squeeze but did it.
 
You should have 120 vac to one of the contacts.
The other side of that contact should be wired to the switch on the front of the water heater.
The other side of that switch should be wired to a contact of the thermostat/hi temp cutout.
The other side of the thermostat/temp cutout should be wired to the heating element.
The other side of the heating element should be connected to neutral (and that neutral wire I believe has a wire connection in the junction box).

That is the 120 vac power routing for the heating element. You can use a voltmeter to start checking for power at any of those points and either work your way upstream or downstream to find the point power is lost. .
 
Bill, I have 120 at the black wire coming into the junction box and black wire to the relay switch. but no 120 at the pin of the relay switch where the black wire goes and leads to the outside on off switch. I put a new relay in junction box. I bought two so I will install another new one. Am I right about there should be 120 at the pin of the relay that leads to the on off switch.
 
You should have 120 vac to only one side of the contact when the relay is de-energized. When energized you should also have 120 vac to both sides of that contact, one side going to the outside black switch.

When the inside switch is activated you should have 12 vdc to the coil of the relay to energize that relay and send 120 vac to the switch.

If you are getting 120 vac to one side of the contact but not to both sides of the contact when you energize the relay, then the relay is bad, or you are not actually getting 12 vdc to the relay to energize it, or the relay coil is not properly connected to ground.

Since you replaced the relay it doesn’t seem likely the relay is bad. Check to see that you are getting 12 vdc to the coil when the inside switch is actuated. If you are and the relay doesn’t energize, then check the ground wire to the coil.
 
Here is the same picture Daryle posted above. Assuming the wire colors shown are accurate, you should see 12 vdc on the orange wire and 120 vac on both black wires when the relay is energized. Yellow wire is 12 v ground. Relay coil is shown in left picture (12 vdc side) and relay contact is shown in right picture (120 vac side). You can use the metal case for your meter ground lead for all measurements since ground and neutral are ultimately bonded at the source.

(Don’t know why text is fuzzy. Pic on my phone is sharp).
.
 

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Strange. That pic is fully focused in my iPhone photo library. But looking at it in uploaded to this thread the text is fuzzy to the point some is hard to read. Same way with the pic in Daryle’s post above. :confused:
 
The photo is clear. Thank you. I'm tired of dealing with it now. Will just use propane.

Inside the trailer the switch to turn the water on is lite up. If it is lite up can there be a problem with it.
 
Hmm
The little switch on the inside of the RV and associated relay should just be for the PROPANE side of the Water Heater.
I had the Nuetral Wire in the Electrical Box on the Side of the Water Heater go bad - started a fire.. Just the coil of the wire nut was left.
I rebuilt the Electrical side with a 20 Amp rocker switch I put on the wall and eliminated the little inadequate rocker switch on the Exterior of the Water Heater (which I had to replace at least once before this rebuild)
The Electric side is really just simple other than the thermostats.
At least that was how it was on my 2005 Big Sky
 
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The 2011 rig will have two rocker switches inside, one for the gas side which goes directly to the thermostat/high temp for the gas , and the other inside switch goes to the electric relay which controls the 120 volt power to the electric side of the water heater.
 
I smelled a burning smell in my 2011 unit years ago and discovered all of the relay and wiring burnt up in that junction box. In my opinion it's just a disaster waiting to happen. I got rid of that box mounted a new box and ran Romex Wire up to the bathroom in the wall where I put 120 volt switch with a red light on it so I know the heater is either on or off. But I still left the little switch outside the heater just as a fail safe
 

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