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One thermostat for multiple systems

I'm looking for the best control solution for my house. I currently have a very old boiler (~1964) with a Lux TX1500 digital programmable thermostat with heat/cool modes and 3 zones (not seperately controlled). In the next year or so I'm contemplating upgrading the boiler to a Navien Combi 240 boiler and sometime after that install a 3 zone heat pump.
I am curious what you would suggest for thermostat controls. When I install all this I would prefer not to have a ton of thermostats all around the house and just have 3 stats for all 3 zones. I would prefer a thermostat that could control the boiler and heat pump in one.
Additionally, is there any option for a smart thermostat to calculate whether it's cheaper to run the heat pump at a given electrical price vs running the boiler at a given LP price, or am I just overthinking this whole thing?
I live in northern indiana where it can get -20F and the heat pump wouldn't be able to keep up by itself.
Thanks for any help!


  • Jamie Hall
    Jamie Hall Member Posts: 23,668
    You should look into the Honeywell RedLINK platform. The technology is well proven and versatile. There probably are ways to configure it to do what you want. It is not inexpensive...

    As far as calculating whether it's cheaper to run one heat source or another at any given time, however... no. It won't do that. However, you could probably do that with a moderately simple but full on, computer such as a Raspberry PI with suitable programming and peripherals.

    Would it be worth the effort? Depends -- if you like to tinker and like computers and programming, might be a fun project. If, on the other hand, you just want the house to be warm and reliably controlled... no. IMHO
    Br. Jamie, osb
    Building superintendent/caretaker, 7200 sq. ft. historic house museum with dependencies in New England
  • mikeg2015
    mikeg2015 Member Posts: 1,194
    A dual fuel thermostat is the best option. Heat pump efficiency depends on outdoor temperature primarily and outdoor humidity
    as, but that’s not typically used.
  • EdTheHeaterMan
    EdTheHeaterMan Member Posts: 8,176
    What Heat Pumps are you looking at adding? Unitary (3 air handlers and 3 outdoor units) or Mini-split with one outdoor unit and 3 indoor heads?

    Because... Mini-split systems don't talk to conventional thermostats... but Unitary heat pumps can talk to conventional thermostats. Honeywell has is a good platform for unitary products and boilers, but you will need someone with more than a basic understanding of HVAC. This is where you get a good contractor with knowledge of advanced control applications. Ask around for recommendations at a local HVAC or Plumbing supply house

    Sometimes your regular plumber or heating professional will have a GO TO guy for the more complicated controls. I have personally assisted about 15 different contractors in my area with "Wiring issues" over the last few years.

    Edward Young Retired

    After you make that expensive repair and you still have the same problem, What will you check next?

  • mikeg2015
    mikeg2015 Member Posts: 1,194