Welcome! Here are the website rules, as well as some tips for using this forum.
Need to contact us? Visit https://heatinghelp.com/contact-us/.
Click here to Find a Contractor in your area.
If our community has helped you, please consider making a contribution to support this website. Thanks!

Should I even think heat pump is an option ?

Options
Dave Carpentier
Dave Carpentier Member Posts: 638
in THE MAIN WALL

Older two story on slab with attached garage. Infloor on the main and garage, air handler upstairs. Design temp is -21f (-29c) and heat loss calc says I need about 70k. No a/c , but we would love to have.

25yr old cast oil boiler now, 110k output. Its running fine, but ya know.. 25 years. Two (of 7) wirsbo valves are stuck open (need new manifold) , needs a new mixer, a couple of the old gate valves are kaput. So, Id like to repipe and go more efficient this summer.

My options seem to be:

  1. New oil boiler, repipe and add buffer tank . Cheapest solution for up-front and long-term maintenance costs, but most expensive for fuel.
  2. New mod/con gas boiler, repipe and add buffer tank. Save a ton on fuel costs, but high up-front and maintenance. Parts for these things are $$$, it seems.
  3. New ccHP (A2W) plus propane Aux heater of some sort , both feeding into a buffer tank. I havent priced this yet, but I suspect it would be large. Fuel cost would be lowest. Bonus: We would get a/c.

I put propane as aux, as going electrical Aux would be pricey anyhow. The existing electrical service is only 125a. Would need new overhead wires and panel (I diy'd original, should have put a 200a panel on.. who knew).

Am I crazy to even think of a ccHP for A2W in this climate ?

30+ yrs in telecom outside plant.
Currently in building maintenance.

Comments

  • hot_rod
    hot_rod Member Posts: 27,065

    Unless your heat emitters can cover the heating load on the design, -21F?? day, with 120F SWT, I would say no. That 70K load is a bit high also.

    Here is some info from Arctic on their cold climate models. A2WHP manufacturers have become a bit more realistic on how their systems can or cannot replace a boiler.

    Screenshot 2026-01-25 at 9.30.40 AM.png Screenshot 2026-01-25 at 9.32.19 AM.png
    Bob "hot rod" Rohr
    trainer for Caleffi NA
    Living the hydronic dream
  • EBEBRATT-Ed
    EBEBRATT-Ed Member Posts: 19,881

    I think you would regret a HP. If you mechanically and electrically inclined a MOD CON would be the best choice.

    Learn your own system and you can do most of the service and maintenance better that most so called techs now.

  • Hot_water_fan
    Hot_water_fan Member Posts: 2,241

    I think the easy solution for upstairs is heat pump + furnace. You don’t need hydronic for forced air.

    Also, how much oil did you use in the last fill? 70kbtu is a LOT.

  • pecmsg
    pecmsg Member Posts: 6,881

    I like the heat pump installed here but change to hot water cast iron radiators when it gets below 35° outside.

  • Gabriel82
    Gabriel82 Member Posts: 10

    @Dave Carpentier I had some photos of heat pumps on the inside...

    It was scary: they are computers big freezers things style "heaters"...

    So much electronics...

    Sure is nice to be able to "call your central heating unit" from 2000 miles away and tell it to start heating.

    But they are complex ,and with no heating back-up I can't even imagine in what temperatures you might have to live in(plus no hot water) if the damn thing fails in minus 10-20 Celcius blizzard...

    You alone ,will not be able to fix it. That I know for sure...

    As for big water buffer storage tanks ,they are indispensable.

    They work like big batteries and store excess heat for at least 12 hours.

    Even if your heater fails you will still have heat +hot water in house for a few hours just using the excess heat energy stored in those big insulated water tanks.

    I tend to be inclined toward energy security and independent problem fixing!

    You can do that in an oil heater.

    I don't see doing that with a heat pump.

    They either work or don't.

    And in a bad weather period how or will the tehnician get to you if the heat pump has a problem?!

    Of course ,it's your choice!

    Bad to the Bone

    Song by George Thorogood & The Destroyers ‧ 1982

  • pecmsg
    pecmsg Member Posts: 6,881

     I had some photos of heat pumps on the inside...

    It was scary: they are computers big freezers things style "heaters"...

    So much electronics...

    The only computer on mine is the T-Stat!

    Minis have quite a few.

    VRF and Commercial have even more.

  • Gabriel82
    Gabriel82 Member Posts: 10

    I've had such problem in a blizzard minus 16 Celcius, no electrical power for about 14-16 hours...

    Because snow was pilling up around 3 meters tall/deep I had to get all my clothes on and wait it out...

    Needless to say ,in spring, I had myself built 2 ceramic tile stoves with natural draft chimneys storage space in house for 2 tons of very dry wood briquettes plus enough firewood for 2 weeks!

    I woke up one Sunday morning next winter, never even knew there was no electrical power + minus 11-12 Celcius outside...

    But felt it on my skin when opened the outside door 😳

    It's good to be warm and safe 😂

    Why depend on others?!

    Bad to the Bone

    Song by George Thorogood & The Destroyers ‧ 1982

Categories