5 ms·

hmm as someone about to purchase a heat pump system for heat in a northern climate I am not sure if I should wait... is this an announcement of a breakthrough

hmm as someone about to purchase a heat pump system for heat in a northern climate I am not sure if I should wait... is this an announcement of a breakthrough or a challenge to find a breakthrough?

zip1234 4y ago
There are already heat pumps that work at very low temps. Mitsubishi has models that are still heating at -13f
boulos 4y ago
FTA, they already measured it and will deploy in 2024: > The prototype delivers 100% heating at 5°F at double the efficiency, and 70% to 80% heating at -5°F and -10°F. DOE’s Oak Ridge National Laboratory validated the performance and efficiency of Lennox’s prototype. > Lennox is one of nine manufacturers competing in the CCHP Technology Challenge. Its product and others that meet the CCHP Technology Challenge will undergo trials in cold climate regions over the next two years to demonstrate performance, efficiency, and comfort when applied in the field throughout a winter. Deployment and commercialization are planned for 2024.
Jgrubb 4y ago
I just bought a Mitsubishi mini split system to replace our oil furnace and bring A/C to our house here in New Jersey for the first time. Their high end outdoor units heat down to -13 F, which is colder than I've ever seen here. It arrives in august. Gree has a system that claims to have full heat down to -31, so I'd say just keep researching and you'll probably be fine.
- throw0101a 4y ago
  > Gree has a system that claims to have full heat down to -31, so I'd say just keep researching and you'll probably be fine. Doing a quick search, they're using 'standard' R410A refrigerant (PDF): * https://www.greecomfort.com/assets/our-products/multi-plus-ultra/documents/multi-plus-ultra-service-parts-catalog-d.pdf https://www.greecomfort.com/assets/our-products/multi-plus-u... the same as everyone else. It seems just that they though it worth the engineering effort to push a little further than most other companies. See anything with the label "For Extreme Conditions": * https://www.greecomfort.com/our-products/ https://www.greecomfort.com/our-products/
- david422 4y ago
  What is the plan for when it gets colder than -13? Do you do a hybrid with your furnace? Some other solution? Thinking of getting some heat pumps myself.
  - leviathant 4y ago
    In nearby Philadelphia, it rarely gets that cold, and not for extended periods of time, but when it does, we bust out blankets and space heaters to make up the difference.
  - sokoloff 4y ago
    I’ve looked into heat pumps pretty extensively for my upcoming boiler replacement (looking at an air-to-water in my case, but very similar principles apply). In my case, the 99% design temperature is high single digits Fahrenheit. For the 3.5 days/year colder than that, the plan is to have the house “coast” on thermal mass. That’s for cases where the ambient temp is below design (where the heater can make heat but just no longer enough to keep up with the building heat loss), not for when it’s below a cutoff (where the heater shuts off entirely). In my case, that’s so far below design temp that I’d expect to never see it. (We hit -9°F in 2016 and would have to go all the way back to 1943 to find a low of -14°F.) If it happened, thermal mass would start to carry us with electric space heating keeping the house from totally freezing.
    - hamandcheese 4y ago
      I might invest in some backup propane heaters as well (a buddy heater at Walmart is pretty affordable and is safe for indoor use). I feel like in blizzard-like conditions having electricity be your backup plan might not be too wise.
  - Jgrubb 4y ago
    We usually switch to the wood stoves once winter sets in. Our forced air furnace is incapable of making the house warm and cozy because duct reasons that I can't really fix. I'm planning on getting rid of it altogether and doing the heat pump(s) most of the year, the wood stoves in winter and reclaiming a lot of headroom in the basement and an entire utility room that the furnace currently takes up.
mjmahone17 4y ago
You probably should not wait: it will be 2 years of testing according to the announcement, and if you’re doing a retrofit most the cost of installation will be installing the transfer lines inside, mounting the unit, etc (opening walls and closing them back up). Transferring from an old outdoor unit to a new one should be a fraction of the original install cost (basically just the new unit cost plus the cost of hooking it up). But, if you’re willing to wait or pay extra for the efficiency gains, you might be even better off getting set up with a ground source heat pump now. The install cost is more up front, but because ground temperature is higher than air temperature in winter and lower than air temperature in summer, the differential you need to pump in or out is a lot less, and therefore much more efficient. I don’t think any air to air heat pump in the next 20 years will be as efficient as a ground to air system you could install now. The air to air systems just have lower up front install costs.
- pbourke 4y ago
  In the US, there is still a 30% federal tax credit for ground source heat pumps as well. Many of the other energy credits have sunset (such as solar, I think) Edit: it’s 26% this year and 22% next year.
newsclues 4y ago
Go ahead as planned but perhaps have the installer plan for a future upgrade when the current device fails
rudedogg 4y ago
If you haven't heard of it, make sure you use https://ashp.neep.org/#!/product_list/ https://ashp.neep.org/#!/product_list/ to help pick a model. One tip from my install, is to go with single zone units. I did a multi-zone and the way the control system works is kind of weird. They also don't have as good of a turndown ratio[0] as smaller/single zone systems, making it less efficient. Overall I'm happy with it though. [0] https://en.wikipedia.org/wiki/Turndown_ratio https://en.wikipedia.org/wiki/Turndown_ratio

hmm as someone about to purchase a heat pump system for heat in a northern climate I am not sure if I should wait... is this an announcement of a breakthrough or a challenge to find a breakthrough?

zip1234 4y ago

There are already heat pumps that work at very low temps. Mitsubishi has models that are still heating at -13f

boulos 4y ago

FTA, they already measured it and will deploy in 2024: > The prototype delivers 100% heating at 5°F at double the efficiency, and 70% to 80% heating at -5°F and -10°F. DOE’s Oak Ridge National Laboratory validated the performance and efficiency of Lennox’s prototype. > Lennox is one of nine manufacturers competing in the CCHP Technology Challenge. Its product and others that meet the CCHP Technology Challenge will undergo trials in cold climate regions over the next two years to demonstrate performance, efficiency, and comfort when applied in the field throughout a winter. Deployment and commercialization are planned for 2024.

Jgrubb 4y ago

I just bought a Mitsubishi mini split system to replace our oil furnace and bring A/C to our house here in New Jersey for the first time. Their high end outdoor units heat down to -13 F, which is colder than I've ever seen here. It arrives in august. Gree has a system that claims to have full heat down to -31, so I'd say just keep researching and you'll probably be fine.

throw0101a 4y ago
> Gree has a system that claims to have full heat down to -31, so I'd say just keep researching and you'll probably be fine. Doing a quick search, they're using 'standard' R410A refrigerant (PDF): * https://www.greecomfort.com/assets/our-products/multi-plus-ultra/documents/multi-plus-ultra-service-parts-catalog-d.pdf https://www.greecomfort.com/assets/our-products/multi-plus-u... the same as everyone else. It seems just that they though it worth the engineering effort to push a little further than most other companies. See anything with the label "For Extreme Conditions": * https://www.greecomfort.com/our-products/ https://www.greecomfort.com/our-products/
david422 4y ago
What is the plan for when it gets colder than -13? Do you do a hybrid with your furnace? Some other solution? Thinking of getting some heat pumps myself.
- leviathant 4y ago
  In nearby Philadelphia, it rarely gets that cold, and not for extended periods of time, but when it does, we bust out blankets and space heaters to make up the difference.
- sokoloff 4y ago
  I’ve looked into heat pumps pretty extensively for my upcoming boiler replacement (looking at an air-to-water in my case, but very similar principles apply). In my case, the 99% design temperature is high single digits Fahrenheit. For the 3.5 days/year colder than that, the plan is to have the house “coast” on thermal mass. That’s for cases where the ambient temp is below design (where the heater can make heat but just no longer enough to keep up with the building heat loss), not for when it’s below a cutoff (where the heater shuts off entirely). In my case, that’s so far below design temp that I’d expect to never see it. (We hit -9°F in 2016 and would have to go all the way back to 1943 to find a low of -14°F.) If it happened, thermal mass would start to carry us with electric space heating keeping the house from totally freezing.
  - hamandcheese 4y ago
    I might invest in some backup propane heaters as well (a buddy heater at Walmart is pretty affordable and is safe for indoor use). I feel like in blizzard-like conditions having electricity be your backup plan might not be too wise.
- Jgrubb 4y ago
  We usually switch to the wood stoves once winter sets in. Our forced air furnace is incapable of making the house warm and cozy because duct reasons that I can't really fix. I'm planning on getting rid of it altogether and doing the heat pump(s) most of the year, the wood stoves in winter and reclaiming a lot of headroom in the basement and an entire utility room that the furnace currently takes up.

mjmahone17 4y ago

You probably should not wait: it will be 2 years of testing according to the announcement, and if you’re doing a retrofit most the cost of installation will be installing the transfer lines inside, mounting the unit, etc (opening walls and closing them back up). Transferring from an old outdoor unit to a new one should be a fraction of the original install cost (basically just the new unit cost plus the cost of hooking it up). But, if you’re willing to wait or pay extra for the efficiency gains, you might be even better off getting set up with a ground source heat pump now. The install cost is more up front, but because ground temperature is higher than air temperature in winter and lower than air temperature in summer, the differential you need to pump in or out is a lot less, and therefore much more efficient. I don’t think any air to air heat pump in the next 20 years will be as efficient as a ground to air system you could install now. The air to air systems just have lower up front install costs.

pbourke 4y ago
In the US, there is still a 30% federal tax credit for ground source heat pumps as well. Many of the other energy credits have sunset (such as solar, I think) Edit: it’s 26% this year and 22% next year.

newsclues 4y ago

Go ahead as planned but perhaps have the installer plan for a future upgrade when the current device fails

rudedogg 4y ago

If you haven't heard of it, make sure you use https://ashp.neep.org/#!/product_list/ https://ashp.neep.org/#!/product_list/ to help pick a model. One tip from my install, is to go with single zone units. I did a multi-zone and the way the control system works is kind of weird. They also don't have as good of a turndown ratio[0] as smaller/single zone systems, making it less efficient. Overall I'm happy with it though. [0] https://en.wikipedia.org/wiki/Turndown_ratio https://en.wikipedia.org/wiki/Turndown_ratio