2 heat thermostat at the same time

Traveler3131

Hello - I need some assistance selecting a proper thermostat for my setup. This is for a camper (travel trailer). I have a Air conditioner with a 2 speed fan, and I have added an electric heat element to the AC as well. There is also the standard propane furnace.

I would like a thermostat that would let me run the heat in three options... #1, electric only, #2, propane only, #3, electric and propane. #2 would only be used if I was at a non-electric site.

I am wondering if I get a thermostat with a heat and EM heat option, and connect my electric heater as the EM option, then I could set it to EM heat for option #1 electric only... and set it to regular heat for option #3 electric and propane... and then if I had no electric service, setting to regular heat should work with only propane.

Will this kind of a thermostat work to run both electric and propane at the same time? Can someone recommend a thermostat that will do all I want with the heat (and of course the AC)... and a bonus would be a way to specify low/high on the fan speed.

Not looking for a wifi/bluetooth/smart thermostat - hoping to just have a simple thermostat with lots of buttons/switches to set exactly what I want.

Thanks for your help!