Originally Posted by Cheesehead
Does the system run on electric when you are plugged in and only use propane when there is no electric. I am very uninformed.
If you have a dual-powered water heater, it can run off of electricity (when available), propane....... or both at the same time.
You have to turn the propane and electric sources on. There may be an inside switch for the propane, and an outside switch for the electric. There could also be TWO inside switches, one for propane, and one for electric. That's what is bad, as Forest River doesn't make all the trailers the same way in this process.
That's why I was asking the steps you are taking. As Caper pointed out, if the water is hot from the electric heater element, then propane has no reason to come on. You can actually leave both switches (propane and electric) on, then if you use a lot of hot water faster than the electric heating element can keep up, then the propane will ALSO fire up and heat the water. Propane is always quicker than electric.
If you have the Suburban dual powered water heater, here is a more detailed explanation: