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Thermostat/Humidistat Selection

WoodEd Member Posts: 3
I recently purchased a home in Michigan and need help finding a new thermostat/humidistat that will work with my equipment. My home is originally equipped with a fuel oil furnace with an in-duct humidifier and an AC unit which is controlled by a mechanical thermostat (heat/off/cool). It also has a separate mechanical humidistat. The previous owners then installed an outdoor wood boiler to use for the primary heat source which has a coil installed in the oil furnace ductwork and is controlled by a separate thermostat that I believe only turns the furnace fan on/off when heat is called for. All 3 of these controllers are located near one another and really look ridiculous. I would like to purchase one programmable thermostat/humidistat that combines what the 3 existing controllers do, something with a simple selector switch that can alternate between Oil/AC(which will be selected during warm months) and the outdoor wood boiler(for use during cold months) and can also control the humidistat. Combining these 3 components will help me get rid of 3 eye sores. Any help is greatly appreciated.


  • SuperJ
    SuperJ Member Posts: 606
    Many of the smart thermostats this days support hum/dehum (they have a built in humidity sensor) as well as multiple stages of heat/cool. You might need to use a couple relays to make things work off the switched 24VAC from the stat.

    You might want to add a 2/3way valve (depending on your pumping arrangement) to the wood furnace coil to gain some control over it.

    The heat can be staged so that wood boiler would be first stage and oil heat only used if the wood heat can't keep up.

    My favorite is the ecobee3/4 (didn't like the Nest I had first). Ecobee offers more control over the configuration, Nest seems to have a superiority complex and won't like you configure things like deadbands.

    Setup would be:
    G = Fan
    R = 24VAC
    C = 24VAC Common
    Y(1) = AC
    W1 = Wood Heating Valve
    W2 = Oil Heat Call

    If you don't have a valve on the wood coil you might just get the stat to cycle the fan on heat 1 (and w1).

    Here is the ecobee compatibity checker.

  • WoodEd
    WoodEd Member Posts: 3
    Thank you for your suggestion and info. I forgot to mention I'm in a rural area without WIFI. Will the ecobee3/4 work without it?
  • SuperJ
    SuperJ Member Posts: 606
    edited May 2018
    They work without wifi, but the experience might be frustrating. I would look into the Honeywell 8000 series stats in your case. There a bunch of models with varying capabilities that look similar.

    You need humidity sensing and control and at least 2 stages of heat 1Cool. If it has more stages of heating or cooling that's not a big deal.

    Something like this would work.

  • WoodEd
    WoodEd Member Posts: 3
    This looks perfect, thank you for your time @SuperJ!
  • SuperJ
    SuperJ Member Posts: 606
    If you have more than one 24VAC transformer be careful with the R wires and common wires. You may want to use relays to keep things separate power wise.