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Dual fuel heating system – thermostat?

ericyancey | Posted in Energy Efficiency and Durability on

We recently built an addition onto our house and instead of extending our existing AC-only system, we installed a second AC/heat pump system. The house also has an oil-fired boiler with baseboards.

We added two heating zones to the addition onto the existing hydronic heating system, so the addition has two heat sources – oil and heat pump.

My question is this – is there a thermostat available that would only fire the boiler when it gets cold enough for the efficiency of the heat pump to drop below a certain rating? Here in western VA it often gets warm enough – like today it is 47F outside – that I believe the efficiency of the heat pump should exceed that of the boiler.

What I would like to have is a thermostat with an outdoor temperature sensor that allows me to use the heat pump when the temps are moderate, and the boiler when it drops below a certain temperature.

Thanks for any help you can provide!

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  1. wjrobinson | | #1

    Vision Pros and most Prestige by Honeywell can be set up to do what you desire. You may want a pro to do so for you.

  2. wjrobinson | | #2

    The heat pump is programed to be locked out at your desired temperature via the tstat.

  3. ericyancey | | #3

    Awesome, thanks AJ! I've been wanting to try out a thermostat that I can connect to my home's network anyway, so it looks like I might be able to find one that will control both systems and be accessible over the network. I'm a software engineer/IT guy so I'm a geek when it comes to hooking things like this up :)

    I'll report back my results once I get it all hooked up.

    Thanks again,


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