I’ve seen a lot of articles claim heat pumps don’t work well below -15c, but they never mention there are ways around that. I live in Canada in an area that regularly gets much colder and a lot of people around here have heat pump systems… the only difference is instead of the other side of the heat pump being outside, we bury them underground below the frost line. (Geothermal)
It does drive the cost up somewhat, but they still end up paying for themselves in the long run. Added bonus is in the summer, most system are reversible and will also cool your house much cheaper than traditional ac units.
Maybe part of the problem is my fear of installing anything “for the long run” because not only do I not want to live here 30 years from now, I can’t imagine myself happy anywhere in the US for a period of 30 years straight.
Aren’t there other supplemental heat options, too? So if it’s “too cold” they can put a gas or electric warmer on the system to bring the temp up. With their 200%+ efficiency it would be like running a space heater.
Ya you could… you’d be better off though just getting a system that suits your location though, but the initial cost is usually the biggest issue. I live where it commonly gets in the -30 to -40c temps, and I know of 25,000 square foot shops with geothermal pumps that stay nice and warm all winter.
Yes, I have an air source heat pump (basically a reversible air conditioner) with typical coils in an air handler with electric resistive heating coils as backup. Essentially, they can work with any backup system, whether it’s an electric or gas furnace, or other space heating units elsewhere.
Unless you have a constant heat source (flowing groundwater), you need to pump heat back into the ground in summer or the system will “freeze up” after a few years. If the heat battery of the ground isn’t being recharged, it’ll eventually die.
Yup we had that problem at a large shop once. The system was still working but it was really struggling one winter. They were previously using heat only (floor heat), so that spring they installed a few radiators with fans for cooling to push more heat back into the ground. Worked great ever since.
Thermal mass storage system in a way.
Ground source heat pumps are not air source heat pumps. They’re not an option for people without either very large gardens for horizontal installation, or access for very large machinery to dig the holes to install them vertically.
The claims you have seen likely came from a pro-carbon lobbyist or someone with a badly-installed heat pump. Air source isn’t as efficient as ground source but they are cheaper to run, as long as the house is reasonably well-insulated, has large enough radiators or underfloor heating, and enough air circulates around the pump.
I live in a shitty house from the 50s in Poland, poorly insulated AND I walk around the house on a t-shirt if I want… the problem is the energy I have to spend. Heat-pumps are not a miracle if your house is poorly insulated.
I’ve been remodeling my house one room at a time, I’m taking insulation very seriously and putting as much as I can. The rooms that I’ve remodeled are so hot during winter while rest of house is freezing, quite annoying for my HVAC system actually, but interesting how much money is just flying away through the walls
If I may suggest you focus on air tightness as well. Insulation isn’t very effective with air flowing through it. If you’ve worn a fleece jacket on a windy day you’ll know what I mean.
That, and vapour penetration through a poorly sealed envelope can lead to moisture issues.
