5 ms·

When will air source heat pumps be ready for service in cold weather climates without gas backup?

boplicity 4y ago
They're available right now -- you can get ones that will heat from -30c. They're less efficient at colder temperatures, though.
dabeeeenster 4y ago
Just had a heat pump installed (Vaillant) - at -1 degrees outside I'm getting a COP of > 2.6. So they are ready.
- sampo 4y ago
  > -1 degrees outside -1F is -18C -1C is 30F
  - ComputerGuru 4y ago
    They're from London, so it's the "not even cold but it's negative" rather than "actually cold and heat pumps aren't a good idea" measurement.
    - Freestyler_3 4y ago
      for those places where the scop is low, you have to drill for heat. If that's not possible then maybe a system where you can burn wood to suck the heat out of that.
rr808 4y ago
I feel a combination with a wood burning stove is best. Especially with the potential for power cuts.
- Scoundreller 4y ago
  Wood pellet stoves are very efficient and semi-automated. Pellets can be cheaper than split logs (if you have to buy them).
  - timbit42 4y ago
    They need a generator when the power goes out though.
rainsford 4y ago
It depends on what you mean by "cold weather", but modern air source heat pumps are getting increasingly efficient in surprisingly cold temperatures. This Samsung model I randomly found from a Consumer Reports link (https://ashp.neep.org/#!/product/65014/7/25000///0 https://ashp.neep.org/#!/product/65014/7/25000///0) claims to still heat almost as effectively well below freezing as it does at more mild winter temperatures. Even for less effective heat pumps, gas backup isn't really a requirement since you can often use electric "heat strip" backup like my home does. Heat strips are not particularly energy efficient, but many places that can get cold during the winter aren't continuously cold, so a less efficient electric backup is just fine.
fulafel 4y ago
Why doubt their existence? There have been good cold climate air source heat pumps for a long time, over 10 years at least.
- timbit42 4y ago
  If you live in Alberta, they still don't exist because you need it to handle -40C or even -50C in winter. The vast majority of Canadians live within 100 km of the US border and don't see temps that low though.
cbrozefsky 4y ago
They are now. In Vermont, we are in our first year with heat pumps. Have a wood stove as backup and supplement when we want to go pantsless mode. The original oil burner is currently turned off, out of commission waiting on some parts. We could go without the wood stove, and have done so for stretches. We installed Mistubishi Hyperheats, 3 external units, 5 heads. Zero interest financing by installer, for about 21k all in including electrical work. Earlier this year we also did air source hot water heater, for about 4k all in. We were spoiled by the whole house air conditioning over the summer, and the heating has been performing just fine. It about doubled our electric consumption, but that bill is still less than my oil bill was, before the price of oil nearly doubled. We're motivated primarily by a desire to minimize fossil fuel consumption, and then to mitigate volatility in fossil fuel markets. With this install we completed electrifying all utilities in the house , and have a rooftop solar array that previously offset the entirety of our consumption, but will not at current levels. The heat pumps will just about pay for the cost difference between them and a new oil burner before their parts warranty is up. Add in the cooling, and the increased control and comfort we have, and it's a pretty sound investment, IMO. As an anecdote, the conversation at the local bar in Rutland, VT the other night was all about people planning to get heat pumps, or promoting them after having them installed. Not wealthy tech enthusiasts, but bartenders, small business owners, and working class families. With the IRA inventives, and the price of heating oil -- it's becoming a normal thing, not an exception.
- 1123581321 4y ago
  I'm curious about the disposition of the local HVAC companies and tradespeople there. Do you feel confident that you could get emergency service in cold weather? I like this technology a lot, but I live in an area where I can't get most companies to take my request for a quote seriously if it's not a standard central air, furnace or water heater. I had to DIY my Rheem heat pump water heater in 2021 because I couldn't get a quote from a plumber.
  - cbrozefsky 4y ago
    All the ones we know of are doing mini splits and heat pump hot water, and we had no problem getting quotes and even recommendations.

They're available right now -- you can get ones that will heat from -30c. They're less efficient at colder temperatures, though.

dabeeeenster 4y ago

Just had a heat pump installed (Vaillant) - at -1 degrees outside I'm getting a COP of > 2.6. So they are ready.

sampo 4y ago
> -1 degrees outside -1F is -18C -1C is 30F
- ComputerGuru 4y ago
  They're from London, so it's the "not even cold but it's negative" rather than "actually cold and heat pumps aren't a good idea" measurement.
  - Freestyler_3 4y ago
    for those places where the scop is low, you have to drill for heat. If that's not possible then maybe a system where you can burn wood to suck the heat out of that.

rr808 4y ago

I feel a combination with a wood burning stove is best. Especially with the potential for power cuts.

Scoundreller 4y ago
Wood pellet stoves are very efficient and semi-automated. Pellets can be cheaper than split logs (if you have to buy them).
- timbit42 4y ago
  They need a generator when the power goes out though.

rainsford 4y ago

It depends on what you mean by "cold weather", but modern air source heat pumps are getting increasingly efficient in surprisingly cold temperatures. This Samsung model I randomly found from a Consumer Reports link (https://ashp.neep.org/#!/product/65014/7/25000///0 https://ashp.neep.org/#!/product/65014/7/25000///0) claims to still heat almost as effectively well below freezing as it does at more mild winter temperatures. Even for less effective heat pumps, gas backup isn't really a requirement since you can often use electric "heat strip" backup like my home does. Heat strips are not particularly energy efficient, but many places that can get cold during the winter aren't continuously cold, so a less efficient electric backup is just fine.

fulafel 4y ago

Why doubt their existence? There have been good cold climate air source heat pumps for a long time, over 10 years at least.

timbit42 4y ago
If you live in Alberta, they still don't exist because you need it to handle -40C or even -50C in winter. The vast majority of Canadians live within 100 km of the US border and don't see temps that low though.

cbrozefsky 4y ago

They are now. In Vermont, we are in our first year with heat pumps. Have a wood stove as backup and supplement when we want to go pantsless mode. The original oil burner is currently turned off, out of commission waiting on some parts. We could go without the wood stove, and have done so for stretches. We installed Mistubishi Hyperheats, 3 external units, 5 heads. Zero interest financing by installer, for about 21k all in including electrical work. Earlier this year we also did air source hot water heater, for about 4k all in. We were spoiled by the whole house air conditioning over the summer, and the heating has been performing just fine. It about doubled our electric consumption, but that bill is still less than my oil bill was, before the price of oil nearly doubled. We're motivated primarily by a desire to minimize fossil fuel consumption, and then to mitigate volatility in fossil fuel markets. With this install we completed electrifying all utilities in the house , and have a rooftop solar array that previously offset the entirety of our consumption, but will not at current levels. The heat pumps will just about pay for the cost difference between them and a new oil burner before their parts warranty is up. Add in the cooling, and the increased control and comfort we have, and it's a pretty sound investment, IMO. As an anecdote, the conversation at the local bar in Rutland, VT the other night was all about people planning to get heat pumps, or promoting them after having them installed. Not wealthy tech enthusiasts, but bartenders, small business owners, and working class families. With the IRA inventives, and the price of heating oil -- it's becoming a normal thing, not an exception.

1123581321 4y ago
I'm curious about the disposition of the local HVAC companies and tradespeople there. Do you feel confident that you could get emergency service in cold weather? I like this technology a lot, but I live in an area where I can't get most companies to take my request for a quote seriously if it's not a standard central air, furnace or water heater. I had to DIY my Rheem heat pump water heater in 2021 because I couldn't get a quote from a plumber.
- cbrozefsky 4y ago
  All the ones we know of are doing mini splits and heat pump hot water, and we had no problem getting quotes and even recommendations.