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alazero's avatar
alazero
Explorer
Sep 30, 2013

Thermostat Help

I have a Atwood Hydro Flame Furnace in my Four Winds Motorhome. I purchased a Honeywell RTH111B. I only have two wires. White and Red.

I called Honeywell. They swear that this thermostat will not work. Only on 24 volt systems. I wired it red to red and White to White and the system seems to work. Is the thermostat running on the 2 AA batteries?
Secondly, I purchased a Hunter Just Right Model number 42995.

I have not wired it, but would be interested in how would I wire this?
I do not have a thermostat for my overhead Air Conditioner. As it has its own thermostat on board.

Any help.

AlaZero

4 Replies

  • alazero's avatar
    alazero
    Explorer
    Oct 03, 2013
    Thanks for you reply.

    It works as wired. I haven't had any cold weather yet to test the difference in running longer and the span difference. It will be more efficiant for sure.
    Thanks again.
    I also now have a Hunter Model 42995 that I don't need. Anyone interested. Shoot me a PM.

    Zero
  • opnspaces's avatar
    opnspaces
    Navigator III
    Oct 02, 2013
    Sounds like you did well. It's pretty hard to mess up a two wire system. If you hook it up wrong things don't work. If that's the case you switch the wires and things generally start to work again.

    Yes they claim it will only work on 24 volts. But as you already found out it really will work on just two 1.5v batteries. :)
  • alazero's avatar
    alazero
    Explorer
    Sep 30, 2013
    Thanks for you reply.

    I have no problem with changing the batteries.

    I will just make it a part of the semi-annual battery change of the fire, smoke, and carbon monoxide detectors.

    Buying Duracell batteries at $.10 each these days locally.

    Just wanted to make sure that I don't miswire something and cause issues or burn something up.

    AlaZero
  • enblethen's avatar
    enblethen
    Nomad
    Sep 30, 2013
    The Honeywell unit should work. bad thing about any digital is they will need to have the batteries replaced. Just need to do this or carry batteries with you.
    The Hunter is not the best for a two wire system. It is more for larger units with heat pumps or utilizes a combination thermostat for heating and cooling. Even the Honeywell is setup for heating and cooling. It also has a fan only switch that can't be used in your installation.
    I replaced my crappy RV thermostat with one of these I picked up from Ace Hardware.
    Lux mechanical thermostats

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