Upgrade of water heater

[MVA]

Forum,

I am considering upgrading my water heater when it needs to be replaced. I currently have the 6 gallon propane fired DSI only model (D). I may upgrade to the propane and electric model (DE).

Couple of questions:
- For the DE model is the 120VAC line on a dedicated circuit and what size (15amp?)
- Would I need to change the control panel to select gas vs electric, or does the DE model automatically choose electric if available like the refrigerator does?
- Other issues not considered yet?

Thanks

[Ron in BC]

Things may have changed but on mine, dual source, the control panel turns on the propane only. The default for 110V use is a switch located on the exterior and is accessed by opening the exterior hatch.

Many of us have added an interior switch so that we can turn on the 110 power without having to go outside and flip the switch.

There are dual panels available but I just installed a dedicated switch with an led close by the water heater.

Ron

[MVA]

Thanks Ron. Is it on a dedicated 15 amp line or in a combined line with other outlets?

[splitting_lanes]

I leave the electric switch on, so when I plug in I have hot water.

There’s a concern that you’ll damage the electric heating element if there’s no water in the hot water tank. I don’t think my hot water tank has ever been empty though. Even if you empty the fresh tank there’s still water in the hot tank. I found one reason to switch it off a couple of times— when the outlet you’re hooking up to trips a breaker, or if you have no need for hot water (ie plugging in at home).

[Ron in BC]

Originally Posted by splitting_lanes

I leave the electric switch on, so when I plug in I have hot water.

There’s a concern that you’ll damage the electric heating element if there’s no water in the hot water tank. I don’t think my hot water tank has ever been empty though. Even if you empty the fresh tank there’s still water in the hot tank.

The hot water tank is routinely emptied as part of the winterizing process and when checking the anode. Best Practices would be not to leave the switch on to prevent damage if the trailer is connected to shore power and it's forgotten that the hot water tank was empty or the tank was emptied and later the fresh water tank was filled but the water pump wasn't run meaning the hot water tank would still be empty.

Yes, the water heater requires a dedicated 15 amp circuit. No biggie, there should be room in the panel. The only shared circuits on my trailer are the converter and fridge.

This is the switch I installed. It's sort of on the path from the breaker panel to the water heater. You can buy ready made ones.

Ron

[alanerickson]

According to electrical diagrams here, it's a 15 amp dedicated.

https://www.escapeforum.org/forums/f...ams-19980.html

[CharlesinGA]

Instead of buying the DE model, get the DEL model instead. It uses a dual switch panel with fault light, and the control is all 12v. None of this 120v switch in one place and the gas/fault light panel somewhere else. You run the 120v wire directly from the breaker panel to the water heater, and a relay internal in the water heater, controlled by 12v DC from the switch panel, turns the electric on and off.

And yes, you can run both electric and propane at the same time for faster heating.

Water heater itself, $429 for the DEL model
https://www.amazon.com/Suburban-Mfg-.../dp/B01N21JVZS

Dual switch panel
https://suburbanrv.com/files/product...r%20101121.pdf

This is a much more elegant solution and the same as what Atwood has done for the past 20 years or so. The installation will require the dual switch panel and probably a 14 or 16 gauge primary wire to be run with the gas/fault/ground wires from the switch panel. Switch panel is found in either black or white.

Wiring diagram for switches.
https://www.rvpartscountry.com/dualw...elsw10del.html





As far as 120v source, Most RV manufacturers will put the water heater and the microwave on the same circuit by themselves. You use either a manual two position switch to select power to either the water heater or the microwave, or again many manufacturers will use an energy management system to provide power to the water heater but when the microwave draws more than an amp or so (lights and touch pad) the load shed switches off power to the water heater. When the MW stops, after 30 seconds the load shed restores power to the water heater.

My SOB trailer had the water heater on a general purpose circuit and the MW on a dedicated circuit, and I changed this by installing a load shed box with both devices on the single dedicated circuit.

This all comes about from a National Electric Code requirement that restricts the number of thermostatic controlled devices in the RV to a max of three unless there is an energy management system installed. NEC also limits a 30 amp system to a max of 5 circuits.

Charles

[MVA]

Thanks Charles for clarifying what the DEL model is versus the DE model. BTW - do you know what the DEM model is?

What did you do with the water heater switch/light that I assume was on your KIB panel. Just leave the original panel or did you replace the KIB panel for a model without the water heater control?

--Steve

[rubicon327]

Originally Posted by MVA

Thanks Charles for clarifying what the DEL model is versus the DE model. BTW - do you know what the DEM model is?

Steve: The DEM model has what they call motor aid. It is a heat exchanger built-in that can be connected to the cooling system of an engine to aid the heating of hot water. This would be for motorhomes only.

[MVA]

Thanks for clarifying.

Appreciate the help from all.

--Steve

[CharlesinGA]

Originally Posted by MVA

Thanks Charles for clarifying what the DEL model is versus the DE model. BTW - do you know what the DEM model is?

What did you do with the water heater switch/light that I assume was on your KIB panel. Just leave the original panel or did you replace the KIB panel for a model without the water heater control?

--Steve

In my case I have a Jensen stove hood that had the switches on it, for the generator and gas WH plus fault light. Bigfoot thought it a good thing to put the switch for the Electric WH 5 feet away and not even label it. I didn't like this and after accidently switching the electric WH on twice with no water in it (still ok though) by throwing jacket, etc on top of the switch I moved it to the stove hood by running an additional wire in the harness.

You could easily remove the gas WH switch and fault light and redirect the wires to the Suburban dual switch panel, and add a wire to the WH to control the electric side of it. Easy to blank the switch hole with something, depending on the size switch, they even make hole fillers for switch holes.

--OR-- space permitting in the existing panel, you could whittle an additional switch hole in it. All that is needed is power off the other switch's supply to the new switch.

Charles

[John in Santa Cruz]

I've had the propane only version for many years now, and never missed having electric water heat. the heater is well insulated, so if you're not using hot water, it hardly ever fires up and when it does, its barely audible even on my 21C when its directly under the bed I'm sleeping on.