I will be dry camping this weekend at the track with the temps forecasted to be lower 90's . . I will be runnning the genny and wondering which setting to put the HW heater on? Last year I just turned it on to gas, buy really did not know any better.... My thought process was that it would have less electrical draw on the genny ...

So that is a very interesting question. Thanks for putting it out here.

Here's the thing, first thing are you planning on leaving the hot water heater on all the time or just when you need it? If you are going to manage the hot water heater to only have it on when you need it will it be when you have the genny on? If you want to leave it on all the time with or with out the genny, gas is the way to go.

Here's my thought. First and for most I was surprised to learn and really enjoy that fact, you can run the HW on both gas and electric at the same time. It really improves (more than halves) the bring to temp time on the hot water.

So if you are wanting hot water fast, fire the genny and turn both the AC and GAS HW switches on. That will give you the best and fastest recovery of hot water. I would then turn the genny off when you are done with it and revert to gas hot water.

If you remember to turn the HW off when you go to sleep, you should have some hot water for most of the night but don't expect to take a full on shower first thing in the morning.

When you fire your coffee pot(s) and/or tea kettle(s) in the morning, switch the hot water on with or with out the genny (see above) and you are good to go in the morning as before but wait to enjoy your coffee or tea first before heading for the shower so the water heater can recover.

That's my experience, anyone else?????

Not sure if you are looking at generator capacity issues or energy efficiency.

From an energy efficiency perspective it would probably be more efficient to run HW on gas as the genny motor is probably inefficient compared to the efficiency loss burning gas to heat water.

If you have capacity issues like we do in 30 amp campsites you can manage the power by selectively running the electrical loads as needed except probably the A/C during the day.

Joe
I would leave on electric while the Gen is on and turn to gas if needed while the Gen is off. You are eating up propane either way. Propane use would be lower with just HW on than running Gen

I think its already said here but run it on both (turn both on).

Assuming yours was like mine where the electric was set high enough to maintain the temp in the tank without the propane coming on. Setting it to run on both will allow it to automatically run on electric whenever your generator is on, and propane when it is off.

Efficiency has no bearing on the issue when the generator is being used to power other things such as AC. At that point, the electricity is already available so its near 100% efficient.

Thank you all, i will set it to both and be done with it..