Dear Dave,
I camp off-grid a lot with no water, just using the generator. Does my hot water heater need water in it while powering my camper with generator? Will it hurt the tank and element? Sometimes it’s right cold outside to be using water. —Michael, 2017 Keystone Bullet Crossfire
Dear Michael,
From what I can find on the Keystone website, they offered the 2017 Bullet Crossfire in seven different floorplans starting with the 1650EX at 19’8” and up to the 2510BH at 29’2”. It looks like all floorplans had a standard 6 gallon Gas/Electric Direct Spark Ignition (DSI) with quick recovery water heater that operates on LP or 120-volt power.
First, a personal comment on “hot water heater”
I have to add this to the discussion, as I was “schooled” many years ago by one of the best technicians in the RV industry who told me there is no such thing as a “hot water heater.” It made him furious when technicians would call for troubleshooting advice and call it that. His reply was: “If the water is hot, you don’t need to heat it. It is a ‘water heater’!” I guess that makes sense.
Types of water heaters
Your model must be Suburban, as you referenced an anode rod. That is a metal rod, typically magnesium, that acts as a catalyst to minerals in the hard water so the tank does not get eaten away and damaged.
Another type of water heater is the on-demand, or instant hot water, models that have a cold line running into the unit and a heating element that provides hot water almost instantly. These should not be activated without water. However, I believe you do not have this unless you installed it as an aftermarket component.
Can you operate the water heater without water
Technically, you could run the water heater on the LP mode without water. It would not damage the tank or anode rod, but it most likely would run almost constantly and waste a lot of LP. The unit has a high temperature cutoff switch (ECO, or Emergency Cut-Off) that most likely would shut the unit off.
You do not want to run the water heater in the 120-volt AC mode without water as it will short out the heating element.
My question
The question I have is, why would you run the unit at all if you are not going to use hot water? Drain the water heater tank and shut it off. You can use anything else in the system with the generator and not worry about the water heater.
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RVDT2768
Funny question of the month.
Hi Tom: The only funny question is the one which wasn’t asked. HA!
Running the water heater, even on propane, would over heat the heat exchanger well before the high limit would kick from the hot air in the tank.
It would be like running your car’s engine without antifreeze. The temp gauge doesn’t move until the engine is destroyed.
My son-in-law did that. He lost the AF, the gauge rose and then went back down when it was empty.
I think what he was asking is: If I run the generator, will it damage the water heater? The simple answer is: No it will not if you don’t turn on either propane or electric power to it. Hmmm? (As usual, great answer and review of the various systems and components Dave).
I’ll give you about 1 minute to run the electric water heater element and then it would be shot
the water keeps the heater from burning out
and running propane will overheat and warp the heating part of the WATER HEATER
JUST DONT DO IT
The correct answer/comment about what to call it must be from someone in the Plumbing industry. Yes, I am a Plumber.