Hello and thanks for reading
I have an Atwood propane furnace, and I want to hook it up to a thermostat.
So I gather that most residential tstats are 24vac but some run off batteries and can be put on 12vdc circuits. Style wise, I like the Honeywell round tstats, but they are either 24v or 120v ac and do not take batteries, so those are not compatible.
I was also looking at a heat only, two wire, thermostat by Emerson (model1E78-140). This one uses batteries and is listed as 24vac, but many customers say that have used it in rv’s. My question with wiring this model, is that my furnace has three wires, not two. The instructions for the Emerson say to connect a white to “w” port and red to “rh” port. These are obviously the wires that would be sticking out of the wall in an existing home or rv.
My furnace’s wires are red 12vdc +, black 12vdc-, and a white labeled tstat.
I’m guessing I run a red and a black from my fuse box to my furnace and run the white from my furnace to the tstat, but where does the red wire called for by the tstat instructions come from? I take it the white is a signal relay wire, but what of the red called for by the tstat instructions? Should that be tapped from the positive line going to the furnace?