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Heat Pumps for Hydronic Baseboard Heat?

Hi Guys,

Do they currently make Heat Pumps to supply hot water to Hydronic Baseboard?




  • Hot_water_fan
    Hot_water_fan Member Posts: 620
    Yes - with caveats. The Idronics journals cover this really well, I’d start there. 
  • iced98lx
    iced98lx Member Posts: 57
    edited June 2
    Hi Pat!

    I'm not an expert, and agree with checking out some articles in Hydronic Journals but last time I searched for Air to Water heat pump there were a few companies doing it with a 2 phase heat pump, and then there were also a few companies doing water -> water (AKA GeoThermal) heat pumps for it.

    A quick google suggests there may be more available now, but here are some links to get you started:




    Most were focused on in-floor due to the lower temp requirements but a few got as high as 150 IIRC which is what I run my baseboards at.

    Hope that helps!
  • fentonc
    fentonc Member Posts: 108
    I've been doing a lot of reading about this as well. I agree with @Hot_water_fan - there is a great Idronics issue about this. There are several air-to-water heat pumps (theoretically) available, although finding someone to install/service them will depend on location. Arctic, Aermec, Spacepak, and Enertech make them, amongst others. There are 'cold-climate' as well as inverter-driven models available, but as others mentioned, they usually top out at like 130-135F as the maximum water temperature. Several of them also have integrated electric boilers, and can supplement as needed.

    For retrofitting a house with hot water baseboard, it's really important to actually understand the heating requirements for your house. 180F seems to have been the standard assumed supply water temperature for many hydronic systems, but many systems are also grossly oversized. Baseboards will still put out heat at lower temperatures, but the output is reduced as the delta between baseboard temp and room temp lowers. There are also 'high output' baseboards (with bigger/more fins), panel radiators and fan coil units that could all be installed to replace/supplement existing baseboards if more output at lower temps were needed. After doing a lot of measuring, my house has enough baseboard that it could probably handle 110F-120F water just fine.
  • PilotPat24
    PilotPat24 Member Posts: 35
    Thanks for all of the great information. I first need to calculate the heat loss for my house and determine how much baseboard I have currently. I'll be back with more information!
  • Hot_water_fan
    Hot_water_fan Member Posts: 620
    Good to hear Pat! Try using this for the heat loss: https://www.greenbuildingadvisor.com/article/replacing-a-furnace-or-boiler
  • Dave H_2
    Dave H_2 Member Posts: 503
    Yes, do your heat loss and get it as accurate as you can. When designing with am Air to Water heat pump, the math is going to be of the upmost importance. Alot of the software has so much fudge it, find the areas where the extra is and minimize it.

    Then as for designing for low temp heat emitters, we recently covered this in a Taco After Dark webinar. Here is the link
    Dave H
    Steve Thompson (Taco)
  • jumper
    jumper Member Posts: 1,866
    Various sorts of baseboard. Fintube needs relatively high temperature compared to cast iron or steel panels. The first is convection while other ones radiate somewhat.
  • Hot_water_fan
    Hot_water_fan Member Posts: 620
    edited June 4
    All baseboards (and radiators) are a mix of radiant and a lot of convection? There’s no reason a heavier baseboard radiates more is there if the surface area is the same? All baseboards can work with low temperature water, it’s just if you have enough BTUs to meet the load.