First Timer 1963
Member
Does the hot water heater run off of electricity as well as gas?
Trying to learn
- Thread starter First Timer 1963
- Start date
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If you have answers, please help by responding to the unanswered posts.
If you have answers, please help by responding to the unanswered posts.
DonTom
Well-known member
Welcome!
To ignite it, I think it needs 12 volts and from there makes that voltage high enough to spark. So it won't work without 12V for that reason alone. After once lit, it should work fine with no voltage.
-Don- Auburn, CA
HueyPilotVN
Well-known member
Some hot water heaters work on both gas and 120 volt electricity.
You can check by looking at the back of your heater for a heating element with an electric cord.
Also look for a toggle switch usually with a light.
If yours does not have a heating element than there are kits for some hot water heaters to retrofit an electric heating element.
You can check by looking at the back of your heater for a heating element with an electric cord.
Also look for a toggle switch usually with a light.
If yours does not have a heating element than there are kits for some hot water heaters to retrofit an electric heating element.
DonTom
Well-known member
I assume you mean some work on gas OR 120 VAC.
IAC, I didn't know any did. Now I wonder if the water heater in my new RV can also run from 120 VAC to save a little propane when I have shore power.
-Don- Reno, NV
HueyPilotVN
Well-known member
Either or both. Recovery ts faster with both and yes you can conserve propane by using 120 volt electric.
Krazeehorse33
Well-known member
I put a retro kit in an old fiver I had on a permanent site. Screwed into the drain plug hole on the water heater then I wired a switch with a light by the sink. Worked great.
Rene T
Site Team
Do you have a Atwood (now Dometiic) water heater or a Suburban. If it’s a Suburban, you had to remove the anode Rod out of the drain hole to install the Hot Rod. By doing that, the wall of the tank is no longer being protected from corrosion. The Atwood does not need to have a anode rod so using the Hot Rod would work fine.
To the OP, Can you give us the make and model of your heater?
Krazeehorse33
Well-known member
Don't know. The fiver is long gone. I know I did NOT remove an anode rod.
Rene T
Site Team
I asked the OP to give us that info about their heater.
Gary RV_Wizard
Site Team
Let's stick to First Timer 1963's question, OK? Branching off to discuss somebody else's installation isn't helpful.
Most water heaters can operate on either propane or 120v electric, but we can't be sure unless you identify your heater make/model, or at least the RV year/make/model. And it requires 12v (battery) power for either one.
Most water heaters can operate on either propane or 120v electric, but we can't be sure unless you identify your heater make/model, or at least the RV year/make/model. And it requires 12v (battery) power for either one.
nibroc
Well-known member
I think that ^^^^^^^^^^^^^^^ sums it up
Isaac-1
Well-known member
Pretty much, most modern RV water heaters operate on propane, but have control / ignition systems that require 12V DC from the batteries to operate, though some small trailers (pop ups, etc.) still have manual light pilot light systems that don't require 12V DC.
In addition to propane operation some will also operate on 120V AC power this allows saving propane when plugged into shore power, this can either be a circa 1,500 watt heating element from the factory, or a 500ish watt "hot rod" kit that screws into the drain fitting. Also a few water heaters also come equipped with a heat exchanger which allows them to heat the water from engine heat in motorhomes when it is running.
In addition to propane operation some will also operate on 120V AC power this allows saving propane when plugged into shore power, this can either be a circa 1,500 watt heating element from the factory, or a 500ish watt "hot rod" kit that screws into the drain fitting. Also a few water heaters also come equipped with a heat exchanger which allows them to heat the water from engine heat in motorhomes when it is running.
Kirk
Well-known member
That is not true. It must have 12V as that is what holds the gas valve open until proper temperature is reached, then removes power to the valve and the flame goes out.
Edd505
Well-known member
+1 best answer
DonTom
Well-known member
Thanks for the info.
I shouldn't make such assumptions as I never even looked at an RV water heater before. So I had no idea about that valve running from 12V.
-Don- Reno, NV
Kirk
Well-known member
The only sure way to answer that accurately would be to know what water heater you have and if it was ever modified. The basic RV water heater that comes standard in mid-price or lower RVs will typically be a model that only heats with propane, but still requires 12V electricity to operate the control system. If you have only 1 on/off switch for the water heater, it probably is propane only. Those that come with both will have either a panel with 2 switches or there will be a separate wall switch(sometimes like a 120v light switch) for the 120V side. Any water heater than can heat from either source will have some means to turn on either the gas &/or the electric heat.
Even if your water heater is one that came without any ability to heat from 120V, if you are not the first owner the previous owner could have added a kit that supplies heat from 120V as several manufactures in the after market sell them.
Larry N.
Well-known member
Not completely accurate. In a TT (Trailmanor, actually) I had a Suburban that ran from Propane if you used the indoor switch, but go to the outside panel and there is a small switch that turns on the 120 V heater so that you can run propane, electric or both, but NO electric switch inside.
CharlesinGA
Well-known member
The most basic models of water heater have a valve/knob and pilot light much like most older water heaters at home. You went outside and turned the knob, lit the pilot, held the knob for a few seconds and then released it and turned it past pilot to normal ops, it lights, shut the door and go back inside. It then cycles on a temp sensor.
Later Atwood and Surburban introduced DSI or direct spark ignition. You flipped a 12v DC switch inside and a 12v DC solenoid opened to let gas thru and an ignitor fired off. With this DSI a fault light was added to show when the heater failed to light and stay fired. If no fire is sensed but it is commanded by the control board, a fault light will illuminate. The DSI heater requires 12v DC to fire the flame when needed and hold the gas valve open.
Then electric heat was added. Atwood installed a 1400 watt element in the back (inside of the RV) of the heater near the bottom and use a small 12v DC operated relay to open and close the 120v AC going to the element. You operate the switch, the relay clicks (listen carefully, you can hear it about 5 secs after you operate the switch) the water then heats, and the electric is cycled on temp sensors via the circuit board.
Suburban installed the element on the outside and a small rocker switch in the lower LH corner of the outside of the heater, kinda hard to get at. You still have to go outside and open the water heater door and operate the switch for the electric element. Many owners and some RV manufacturers installed heavy duty "snap switches" inside and ran the 120v thru this switch to keep from running outside to turn the heater on and off. Some where along the line, Suburban also copied Atwood and on some models installed a 12v controlled relay to switch the 120v AC on and off.
Some water heaters used in motor homes have a heat exchanger built into them that allows engine coolant to be run via heater hoses, to the water heater, and thus you always have hot water when the engine is running. My 2007 Winnebago View had a heat exchanger water heater installed but the hoses were not run.. You will find this is the case with many water heaters in motor homes. I recently saw a pic of one posted on a forum with the nipples for the heat exchanger not connected to anything.
As far as control switches, the DSI models will have a rocker switch for the gas and a failure light fed from the circuit board that tells you the heater didn't light off. Newer control panels have both switches and the fault light combined in one panel, but on my 2007 Winnebago motor home, the gas switch and the fault light were built into a control panel with fluid levels, water pump, etc, while the electric switch was a separate switch, illuminated but still a 12v control.
My 2008 Bigfoot trailer was similar in that the gas switch and fault light are on the stove hood (which is a great place for them actually) but for some odd reason, they (like Winnebago) mounted the large, red, illuminated 12v control swtich for the electric, some 5 ft away at the far end of the counter. After accidentally operating the electric switch with no water in the tank (still works, miracle of miracles), not once, but twice, I installed a combined switch panel in an out of the way spot as a temporary measure.
Recently I noticed that the stove hood had another switch knockout open under the printed overlay and so I disassembled cabinets and everything imaginable and ran the extra wire needed (in the harness with the other wires) for the extra switch and installed an illuminated switch, in addition to replacing the gas switch with an illuminated one, in the stove hood.
Moral of this is that the OP, with what was originally a fairly high dollar motor home, probably has both gas and electric water heat, and possibly engine to water heater heat, but given the vintage, or the brand of water heater used, the switches could be anywhere.
The first pic is not my trailer but a later model just like it inside. The lower, red circle is where the combined water heater switches are located on newer models. The two orange circles joined together show where the switches were located on my 2008 model, one on the stove hood, and one on the top of a storage cabinet at the end of the kitchen counter.
The second pic shows the final result of running one wire and installing the red switch and replacing a black switch with a blue illuminated switch. Being on the stove hood is super convenient, as the generator hourmeter and start/stop switch are also located there, and the water pump switch is located to the left of the stove hood, close by.
Third pic shows a typical Atwood/Dometic combined water heater control panel commonly used today in many RVs.
Charles
Later Atwood and Surburban introduced DSI or direct spark ignition. You flipped a 12v DC switch inside and a 12v DC solenoid opened to let gas thru and an ignitor fired off. With this DSI a fault light was added to show when the heater failed to light and stay fired. If no fire is sensed but it is commanded by the control board, a fault light will illuminate. The DSI heater requires 12v DC to fire the flame when needed and hold the gas valve open.
Then electric heat was added. Atwood installed a 1400 watt element in the back (inside of the RV) of the heater near the bottom and use a small 12v DC operated relay to open and close the 120v AC going to the element. You operate the switch, the relay clicks (listen carefully, you can hear it about 5 secs after you operate the switch) the water then heats, and the electric is cycled on temp sensors via the circuit board.
Suburban installed the element on the outside and a small rocker switch in the lower LH corner of the outside of the heater, kinda hard to get at. You still have to go outside and open the water heater door and operate the switch for the electric element. Many owners and some RV manufacturers installed heavy duty "snap switches" inside and ran the 120v thru this switch to keep from running outside to turn the heater on and off. Some where along the line, Suburban also copied Atwood and on some models installed a 12v controlled relay to switch the 120v AC on and off.
Some water heaters used in motor homes have a heat exchanger built into them that allows engine coolant to be run via heater hoses, to the water heater, and thus you always have hot water when the engine is running. My 2007 Winnebago View had a heat exchanger water heater installed but the hoses were not run.. You will find this is the case with many water heaters in motor homes. I recently saw a pic of one posted on a forum with the nipples for the heat exchanger not connected to anything.
As far as control switches, the DSI models will have a rocker switch for the gas and a failure light fed from the circuit board that tells you the heater didn't light off. Newer control panels have both switches and the fault light combined in one panel, but on my 2007 Winnebago motor home, the gas switch and the fault light were built into a control panel with fluid levels, water pump, etc, while the electric switch was a separate switch, illuminated but still a 12v control.
My 2008 Bigfoot trailer was similar in that the gas switch and fault light are on the stove hood (which is a great place for them actually) but for some odd reason, they (like Winnebago) mounted the large, red, illuminated 12v control swtich for the electric, some 5 ft away at the far end of the counter. After accidentally operating the electric switch with no water in the tank (still works, miracle of miracles), not once, but twice, I installed a combined switch panel in an out of the way spot as a temporary measure.
Recently I noticed that the stove hood had another switch knockout open under the printed overlay and so I disassembled cabinets and everything imaginable and ran the extra wire needed (in the harness with the other wires) for the extra switch and installed an illuminated switch, in addition to replacing the gas switch with an illuminated one, in the stove hood.
Moral of this is that the OP, with what was originally a fairly high dollar motor home, probably has both gas and electric water heat, and possibly engine to water heater heat, but given the vintage, or the brand of water heater used, the switches could be anywhere.
The first pic is not my trailer but a later model just like it inside. The lower, red circle is where the combined water heater switches are located on newer models. The two orange circles joined together show where the switches were located on my 2008 model, one on the stove hood, and one on the top of a storage cabinet at the end of the kitchen counter.
The second pic shows the final result of running one wire and installing the red switch and replacing a black switch with a blue illuminated switch. Being on the stove hood is super convenient, as the generator hourmeter and start/stop switch are also located there, and the water pump switch is located to the left of the stove hood, close by.
Third pic shows a typical Atwood/Dometic combined water heater control panel commonly used today in many RVs.
Charles
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Edd505
Well-known member
hers mine on a 2017 on a Suburban WH. Dual thermostats, I have one removed here they are under the little black rubber buttons. This was corroded under and likely did not need replaced. 
OP
OP
First Timer 1963
Member
I tried to find the make and model but there's nothing that told me. So I took a photo, but when I go to post it here, it says its too large. Thank you for trying to help though.
