Furnace Question

[KWLKS]

I have only been using the propane to run the hot water heater for my 2017 Montana 3711FL. The tanks recently rN dry,so I took them to be refilled. When I returned to the trailer, I heard a strange sound coming from under the stairs. It was actually coming from the furnace and the refilled tanks had been reconnected. It sounded like the igniter was constantly trying to light the furnace, even though the thermostats were set to off. I ended up pulling the furnace fuse to get it stop. After connecting the propane tanks, I replaced the fuse, and the same sound started again. I lit all of the burners on the stove, and still get the same sound from the furnace.

All suggestions or comments would be appreciated.

[Ken / Claudia]

I would have done what you did. I make sure the stove burners run for minutes to be sure propane is thru out the pipes after a change. Just to prevent the HWH, furnace or refer start up problems. In your case, I would go out to the hot water heater, open the cover and look and listen after turning on the switch.
If it making clicking sounds, that is the ignitor. It will click a few times, if it cannot start it stops trying. If it fails to start it normally is due to no propane. Caused by #1 no propane, #2 ignitor plugged or broken. I think you know the sound of it heating water, it sounds like a jet engine. And the light on the switch comes on. Others may come up with other ideas. I have not had problems beyond what I mentioned on newer RVs.