Click here to Find a Contractor in your area.
Welcome! Here are the website rules, as well as some tips for using this forum.
Need to contact us? Visit

Mini Split with HyperHeat

Hello, I have steam heat and when we get those really cold days below say 15F my boiler runs nonstop and has trouble trying to get past 60F . (past 55 in the zero days). I was toying with having a mini split to help on the coldest of days but one AC pro told me that to be honest it won't help on those days? Is this true? I know they say they can heat up to like 30 below but he installs them all the time and says no? Thoughts?


  • ratioratio Posts: 1,667Member
    Heat pumps work by taking the heat from outside the building and moving it into the building. As it gets colder outside, heat pump performance drops off. I think your money would be better spent on finding out why your existing boiler can't keep up. A boiler that is too small is quite uncommon. Is it completely silent when it's operating?

    Post a few pics if you can.

  • nicholas bonham-carternicholas bonham-carter Posts: 7,506Member
    Your steam boiler should be capable of keeping you warm, so as Ratio suggested, post some pictures of the boiler label, above boiler piping, and some radiators.—NBC
  • GBartGBart Posts: 645Member
    edited October 11
    Past 60??? Are you starting off at 40?? are you setting the heat way back?? Steam kicks butt, something in the story is missing big time.

    Why do I get the feeling someone cranked the pressuretrol and there's a traffic jam on the hiway?
  • KC_JonesKC_Jones Posts: 3,815Member
    I just skimmed through some of your older posts. Have you addressed any of the past issues at all? I saw mention of only have one venrite #35 main vent. I seriously doubt if that is adequate. There is certainly something going on here that isn't correct.
    2014 Weil Mclain EG-40
    EcoSteam ES-20 Advanced Boiler Control
    Boiler pictures updated 2/21/15
  • Steve MinnichSteve Minnich Posts: 2,121Member
    I agree that your steam system should be more than adequate if working properly

    For what it’s worth, Mitsubishi hyperheat works very well in cold climates. I’ve done small office buildings with them as a replacement for electric heaters, in Chicago, as the only source of heat.
    Steve Minnich
Sign In or Register to comment.


It looks like you're new here. If you want to get involved, click one of these buttons!