Water heater questions

[Rjpetr65]

Hi all,

I have a Suburban SW6DE water heater and have a few questions:

1. There is a switch on the lower left corner of the WH that turns the electric element on and off. When I am plugged-in at an RV park and don’t need hot water, should I turn that switch off or should I just leave it on all the time?

2. Are the gas and electrical systems on the WH independent of each other? I.E. If I turn on the inside switch for the gas portion of the water heater, will it start up if the electrical element is also turned on via the switch on the water heater itself? Can you use both at the same time or do you have to have one system off to use the other? I’m asking because I turned on the hot water switch inside and the ignition did not light, yet I had hot water because the electrical element was turned on. I’m thinking that I should have turned off the electrical element if I wanted to use gas instead of electric?

Thanks
Rich

[AudiDudi]

1. I always left mine on.


2. You can run both electric and gas at the same time. It greatly speeds up the time required to get hot water.

[cavie]

Originally Posted by Rjpetr65

Hi all,

I have a Suburban SW6DE water heater and have a few questions:

1. There is a switch on the lower left corner of the WH that turns the electric element on and off. When I am plugged-in at an RV park and don’t need hot water, should I turn that switch off or should I just leave it on all the time?

2. Are the gas and electrical systems on the WH independent of each other? I.E. If I turn on the inside switch for the gas portion of the water heater, will it start up if the electrical element is also turned on via the switch on the water heater itself? Can you use both at the same time or do you have to have one system off to use the other? I’m asking because I turned on the hot water switch inside and the ignition did not light, yet I had hot water because the electrical element was turned on. I’m thinking that I should have turned off the electrical element if I wanted to use gas instead of electric?

Thanks
Rich

Yes you can use gas, electric, or both. Both will give you quicker recovery. I leave the outside switch off as I use gas. NEVER turn the electric on with no water in the tank.

[5picker]

Originally Posted by cavie

Yes you can use gas, electric, or both. Both will give you quicker recovery. I leave the outside switch off as I use gas. NEVER turn the electric on with no water in the tank.

^^This^^

[Iwritecode]

We have a really informative guide here on FRF:

http://www.forestriverforums.com/for...ore-36197.html

[Rjpetr65]

Thanks.

[paverdave]

Are you saying that the water heater does not light on gas and the only way to get hot water is with electric?

[emm-dee]

The amp draw for the WH is about 10 amps. Add in your air conditioner and converter and you’re approaching 30 amps. If you have a 30 amp RV you’re going to trip a main breaker when the microwave comes on.

Not a problem but something to consider.

[Dominnic11]

Very good question! I have the same water heater in my 2004 Forest River Georgetown 359t motorhome. You can use both the gas and electric at the same time if you need to heat water very rapidly. I always leave the switch in the off position unless I plan on using the electric heat. The reason you ask? If by chance you should happen to drain your water heater tank while winterizing or cleaning out the sediment doing routine maintenance while plugged in or using the generator, the element will instantly burn out since there is no water to limit the heat build up. I alternate using both gas and electric just to give both a workout and to ensure that both are working properly. I bought my motorhome used and the previous owner must have drained with the tank on as the element was burnt and melted. about $10 to replace plus another $7 for the socket to remove the element. An easy job to replace but a little care will prevent this. Hope this information helps. By the way I don't see much difference in the speed the water heats using gas or electric. I think its about the same. Propane is more expensive then electricity but if electricity is not available then you have no choice. Also note, some models have a lighted switch which makes it easy to see, mine does not so I have to be extra careful to see the switch position. Both units work independent of each other and should work using either or at the same time. The gas my not have fired because the electric had already heated the water and prevented the gas from firing. There is a temp control which will maintain the heat but not over heat. That's why at night you can hear the gas water heater cycling on and off all night.

[Rjpetr65]

Thanks for all the info! Yes I did have a problem. Long story let me sum up:

1.Drained tank, replaced anode.
2. Found that the element wasn’t heating up with the switch on. No AC voltage at element. Element reads 10,5 ohms which is good. Replaced the switch in the water heater. Still no aC volts on element. It didn’t trip the overheat sensor as far as I could tell. Pushed reset button anyway. Still same thing. Breaker is fine. Gave up at this point instead of trying to track down a wire, loose crimp etc.
3. Tried the gas DSI system and it didn’t work. Walked outside, turned the switch in the water heater off, tried the DSI switch inside the rig again and voila, it started and heated the water using Propane.
That’s why I asked if they are dependent on each other or not.

The really weird thing is that the element started working by itself today when yesterday it didn’t have any voltage on it.

I’m perplexed how the heating element can just start working by itself today when it had no voltage yesterday. Then the DSI started working after turning the water heater element switch off. Which shouldn’t matter if independent.

Sorry for the length of the response but this is an interesting (albeit odd) set of circumstances.

[jd50i]

Neither electric or gas will come on if the water is up to temperature. If you have electric and gas turned on and you use hot water, the electric and gas will turn on when the water in the hot water tank drops below a set temperature.


The element will not have voltage on it until the water temp drops and the thermostat sends power to the heating element.

[wmtire]

Originally Posted by Rjpetr65

Hi all,

I have a Suburban SW6DE water heater and have a few questions:

1. There is a switch on the lower left corner of the WH that turns the electric element on and off. When I am plugged-in at an RV park and don’t need hot water, should I turn that switch off or should I just leave it on all the time?

2. Are the gas and electrical systems on the WH independent of each other? I.E. If I turn on the inside switch for the gas portion of the water heater, will it start up if the electrical element is also turned on via the switch on the water heater itself? Can you use both at the same time or do you have to have one system off to use the other? I’m asking because I turned on the hot water switch inside and the ignition did not light, yet I had hot water because the electrical element was turned on. I’m thinking that I should have turned off the electrical element if I wanted to use gas instead of electric?

Thanks
Rich

The previously posted link should explain it all. The electric and gas portions are indeed independent, each with their own separate thermostat, that controls each side.

If the electric is on, and the water is already heated...then the gas side will not come on when it's switch is turned on, as there is no need to. The water is already hot.

Now if you do the dishes, take a shower or use hot water quickly, etc...and the water temp drops in the tank...then the gas side will come on since the electric can't reheat it fast enough. Once the temp comes back up to 130 degrees, both sides thermostats turn off again.

If the thermostats are off(open) due to the water temp being 130 degrees you will not have power past that point. Only when they close, does power go to the electric element or gas controls.

[Rjpetr65]

I believe that I would have AC volts at the switch though, which comes right off the breaker right? I had no ac voltage at the switch (I know enough not to try to measure across the switch. I measured from both legs of the switch one at a time to neutral.

[Flybob]

The thermostats on the water heaters are not precision ( don't need to be). This means that if both systems are turned on in one unit the propane side will turn on at a lower temp than the electric side and in another unit it will be opposite. Same is true on the shut off side.

[Mr. Dan]

Originally Posted by Dominnic11

Very good question! I have the same water heater in my 2004 Forest River Georgetown 359t motorhome. You can use both the gas and electric at the same time if you need to heat water very rapidly. I always leave the switch in the off position unless I plan on using the electric heat. The reason you ask? If by chance you should happen to drain your water heater tank while winterizing or cleaning out the sediment doing routine maintenance while plugged in or using the generator, the element will instantly burn out since there is no water to limit the heat build up. I alternate using both gas and electric just to give both a workout and to ensure that both are working properly. I bought my motorhome used and the previous owner must have drained with the tank on as the element was burnt and melted. about $10 to replace plus another $7 for the socket to remove the element. An easy job to replace but a little care will prevent this. Hope this information helps. By the way I don't see much difference in the speed the water heats using gas or electric. I think its about the same. Propane is more expensive then electricity but if electricity is not available then you have no choice. Also note, some models have a lighted switch which makes it easy to see, mine does not so I have to be extra careful to see the switch position. Both units work independent of each other and should work using either or at the same time. The gas my not have fired because the electric had already heated the water and prevented the gas from firing. There is a temp control which will maintain the heat but not over heat. That's why at night you can hear the gas water heater cycling on and off all night.

The highlighted situation is never a problem for me because I'm looking straight at that switch when I'm removing my anode rod - which his how I drain my water heater. It's never a problem for me anyway since I turn off that switch when I unhook from shore power when I leave a campsite. It does me no good having it on while I'm traveling to the next spot.

[5picker]

Originally Posted by Rjpetr65

Thanks for all the info! Yes I did have a problem. Long story let me sum up:

1.Drained tank, replaced anode.
2. Found that the element wasn’t heating up with the switch on. No AC voltage at element. Element reads 10,5 ohms which is good. Replaced the switch in the water heater. Still no aC volts on element. It didn’t trip the overheat sensor as far as I could tell. Pushed reset button anyway. Still same thing. Breaker is fine. Gave up at this point instead of trying to track down a wire, loose crimp etc.
3. Tried the gas DSI system and it didn’t work. Walked outside, turned the switch in the water heater off, tried the DSI switch inside the rig again and voila, it started and heated the water using Propane.
That’s why I asked if they are dependent on each other or not.

The really weird thing is that the element started working by itself today when yesterday it didn’t have any voltage on it.

I’m perplexed how the heating element can just start working by itself today when it had no voltage yesterday. Then the DSI started working after turning the water heater element switch off. Which shouldn’t matter if independent.

Sorry for the length of the response but this is an interesting (albeit odd) set of circumstances.

Those circumstances certainly are odd and as you mentioned should have no bearing on each other.

One other thing, most water heaters are not wired directly to the breaker but rather to a pigtail that plugs into an outlet. (not all but a majority)

There have been reports of the plug not being plugged in, not making good connection and the wiring to the outlet having issues.. I'm not suggesting this is your issue but rather something else to check on an intermittent issue.

The 120v current flow is pretty simple on these water heaters so if you have power at the switch and no power at the element, the only thing in between are the thermostat and high limit switch assembly (w/thermal connector wire) and the wires themselves. Pay attention to the thermal connector wire that connects the thermostat with the high limit switch. You can't see it unless you remove the rubber cover. NOTE: The connector wire 'may' not be thermal but I was always told it is.

[Rjpetr65]

Ok mystery solved! Turned off the power at the pedestal and popped the WH circuit breaker out. The wire was disconnected on the back of the breaker (or was loose) which explains why the electric portion of the WH kicked on once in a while. Secured the wire into the breaker again and all is well.

[KyDan]

In that case I highly recommend you again unplug from the power post and check all breakers for tight wires and then go over the neutral buss and any other wires you can find in the power center that are under screws.


And thanks for the followup. So often we don't get to hear the rest of the story!