Interested in heat pump for A/C but is it reliant during New England winters?
Hi there,
We recently moved into a colonial home in Massachusetts and are looking into air conditioning options. The house (built in 1997) already has ductwork and central heating and runs on oil. We were advised by MassSave to look into heat pumps if we wanted A/C and were told by an HVAC company that our home would need dual heat sources (heat pump + oil or heat pump + propane) and were quoted for it costing upwards of $15k.
My questions are:
– Would it be possible to have just a heat pump and no propane or oil for living with cold New England winters?
– Does $15k sound like a standard price for this?
I’m open to hearing any other advice as well. Thank you!
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Replies
mbp,
My understanding is that the performance of cold weather heat pumps is adequate for New England winters without back up. You may find these articles useful:
https://www.greenbuildingadvisor.com/article/do-heat-pumps-work-in-minnesota
https://www.greenbuildingadvisor.com/question/best-cold-weather-multi-position-whole-home-heat-pump
https://www.greenbuildingadvisor.com/article/in-floor-radiant-heat-vs-cold-climate-heat-pump
https://www.greenbuildingadvisor.com/article/heating-historic-houses-with-heat-pumps
Thank you! Those articles are helpful.
$15k seems about right! Labor + overhead +margin for air conditioning isn’t cheap (or is too cheap, depending on your perspective). You can use fossil backup if needed or resistance backup (really depends on electric panel capacity). Remember, ideally backup should only be used a handful of days per year, so fuel cost shouldn’t matter much.
Use this to size the system if you can get oil usage from the supplier: https://www.greenbuildingadvisor.com/article/replacing-a-furnace-or-boiler
+1 on doing a fuel usage based calculation.
New England is warm enough that any decent hyper heat can carry your place without any backup heat. I'm in a bit colder climate than you and there is no need for even strip heaters with the right unit.
Look for the Trane/Mitsubishi units:
https://ashp.neep.org/#!/product/33540/7/25000///0
or Carrier/Midea:
https://ashp.neep.org/#!/product/33268/7/25000///0
Carrier's own Greenspeed unit will also work:
https://ashp.neep.org/#!/product/31688/7/25000///0
Thank you! I appreciate it. We'll look into these.
Our only heat source in Maine, between Augusta and the coast, is a pair of Fujitsu cold climate heat pumps. Seven winters, no issues.
Great to know - thank you!
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Thank you! They updated the quote to be just over $26k so we are definitely looking into other options.
Ouch. Keep in mind that a heat pump and an AC are near identical pieces of equipment - so if the quotes differ greatly it’s not from it being a heat pump.
Our only heat source for 3BR 2BA home on Cape Cod, MA is two Fujitsu installations. Mini split in main living area, and second installed later with three heads for each of three bedrooms. These replaced an oil boiler. There was a MA SAVE financial incentive to remove previous (failing) oil heating equipment. No problems at all with insufficient heat or AC. New mini splits are better tuned to cold weather operation to handle even sub-zero temps.
Traditional HVAC companies installing mini splits often do not evaluate the actual heating and AC requirements of the building, and grossly oversize the units “to be safe”. So Paul and Akos recommendations to estimate your actual heat losses is essential. Show contractors your calculations to push for right-sized units.
Note that one option that you may have is to have a heat pump as a replacement for your central oil furnace, and continue to use your existing ductwork.
We left the oil furnace in place, and added one mini split in the main living area. When the furnace failed, we added another outside compressor unit and three heads in three bedrooms (single story home). It is typically not the best choice to have individual heads in each bedroom (but GF insisted on individual thermostats per bedroom not one ducted head to bedrooms). Had to insist that the installation company to get the smallest heads available (7kBTU) for three bedrooms. They are way oversized for individual bedrooms, but they have worked out okay. Its best for dehumidification to have units sized only as large as necessary. Otherwise, they cool the area quickly and shut off, rather than run at a lower speed for longer to dehumidify better.
For a two story Colonial, you might choose to have one ducted mini split head to service upstairs bedrooms, and another head downstairs, located in the central living area. You could have it all run off a single outdoor compressor unit. The type and number of indoor heads depends upon your floor plan and preferences. Generally, heating downstairs will heat the upstairs to some extent (hot air rises). Air conditioning the upstairs will cool the downstairs to some extent. (But not vice-versa.) So for a two-story Colonial, you probably want at least two heads, one up and one down.
Note that it you can buy a portable electric heater for backup or for the occasional extremely cold events. Or install small electric heating elements (e.g., “towel” heater) in a bathroom. Heating your entire home with electric resistance heating is expensive. But occasional use makes sense, as electric spot heating is cheap to purchase, not much cost for occasional use.
Thanks so much for this!