Combination propane electric water heater

[Pecos Pete]

We just purchased a 34' classic that has a combination gas/electric water heater. Have had several Airstreams with gas only. Have read all about the workings of the unit. I am curious about what others do with similar heaters.

- The manual says it can be used on electric or gas or both. I have tried gas only and electric only and found the electric to provide hotter water. When both are used the recovery time is very fast. How do you guys use your unit?

- As far as I can tell there is no thermostat on the water heater. Correct? The water is VERY hot on the electric setting.

- Is the life of the water heater affected by either setting?

Looking forward to hearing about your experience.

Thanks! Pecos Pete

[Amsterdamer]

Our previous SOB TT had a gas/electric water heater. I was advised to insure that I never turn on the electric element with a dry tank. The heating element will burn out very quickly in a dry tank. When I wasn't using it, I would trip the breaker to insure it would not get turned on accidentally. I think the recovery time (reheat time) is faster on gas, but electric is often "free".

[lewster]

Amsterdamer,

You CAN use a water heater with both the LP and electric on. It is simply using both sources as needed to heat the water and will give you quicker recovery on high demand for hot water. That said, you might want to conserve LP while hooked up at a campground, or might encounter a situation where those extra 1500 (or so) watts that the heater element consumes might be better spent on air conditioning and other AC requirements, like a microwave or other hi draw appliances if you're in an amperage challenged situation.

YOU have the choice and flexibility of which heating source to use for your hot water.

[Amsterdamer]

Originally Posted by lewster

You CAN use a water heater with both the LP and electric on. It is simply using both sources as needed to heat the water and will give you quicker recovery on high demand for hot water.

Sorry, I didn't mean to imply that you can't use both gas and electric at the same time, that's OK. Just be sure there is water in the tank if it is turned on since the electric heating element will burn out if it is dry.

I also agree that you need to have a good power hookup to use the electric element. If you don’t have 30 amp power, you’ll draw too much if multiple high draw devices turn on at the same time.

[SafeHarbor]

After I bought the '79 Excella, I discovered that a PO had put a gas/electric water heater in the trailer. The wires were run forward to the galley, but never hooked up. At frist, this looked like a present to me. Then I realized that I'd never be able to run the air conditioner AND the water heater at the same time. Living in Dixie made me choose the AIR. The water heater later went POOF in my face when lighting, and I got a STRONG urge to replace it. The new one has an igniter and inside switch, as I guess your '07 surely must.

Actually, I don't know of a reason both sides couldn't be run at the same time for rapid recovery.

Lamar

[lewster]

........may be the solution to your problems. It is propane fired and TANKLESS, meaning that there is no tank to keep hot. It is on only when a hot water faucet is opened and it instantaneously heats water until you are finished. You don't waste a lot of propane, but you sure can run thru a lot of water taking those 45 minute showers (hooked to city water of course!)

I have one in my CCD and during the 3 months I lived in it this past summer, I only used just under one 30# LP tank.

[Mike Lewis]

Pete-- here's the way we use ours. if the site we have has electric included in the site rent we use electric only. If we're metered on electric we use propane{propane is cheaper per BTU}. If we are showering, especially one after another we use both and never run low on hot water. Yes electric is on a thermostat also. ------pieman

[Pecos Pete]

I am using the heater the same way. I have looked in the manual and on the heater but cannot find a thermostat. The water on electric seems way to hot to me. Where is the thermostat?

[87MH]

Originally Posted by Pecos Pete

I am using the heater the same way. I have looked in the manual and on the heater but cannot find a thermostat. The water on electric seems way to hot to me. Where is the thermostat?

Pete:

Even though your question is a few weeks old I guess you still need an answer. I am answering assuming you have an Atwood unit.

The thermostat is on the back of the unit midway between the cold water inlet and the hot water outlet.

It is preset at 140 degrees and is not adjustable.

Integral to the thermostat is a high temp cutoff. If the high temp cutoff should activate, due to either the LP burner heating the water too high or the electric element staying on too long, it has to be manually reset.

The manual reset is located in the middle of the electric thermostat/electric element connection box. You will find a small hole when you look at the terminal box on the backside of the WH. The Atwood manual says to press the eraser side of a pencil into this hole to reset the High Temp Cutoff. I'm not sure exactly where the high temp is set, but for some reason I seem to remember 160 degrees - might be wrong on that.

THere is no reason you cannot run both heat sources at the same time. The hot water recovery time is much less when both heat sources are used together.

[crestonrv]

the thermostat for elect is on back under box on most newer models, note that elect mode pulls about 8 amps and will overload 30 amp service if a/c or microwave are on (converter is always on & pulls 3-6 amps)a/c needs 15 in run but substantially more to start comp. as it cycles with element on you could deprive a/c and cause a slow start which could blow breaker.t-stat is fixed 140 high limit is 180 also refer pulls appx. 2 amps ac

[Alumatube]

On our 1976 Coachmen we had a 6-gal propane-only heater. Brad installed one of those electric calrod heaters to give it a boost, and we were quite pleased with the results. It would heat the tank faster and more quietly than the propane. Not sure of the current draw, but it never affected us since we were either on an all-included fulltime site or paid $20 for the weekend for power at the race track.

Susan