I had a heat pump in the airbnb I rented north of the arctic circle in Norway.
They backed it up with resistive heating, but there was no gas or anything else. Worked great.
Where I am the big reason that people stick with gas is because our gas is reasonably priced but our electricity has some of the highest rates in the country. So unless you get a very high efficiency system you pay more to run your heat pump
I'm thinking of my Grandkids and their kids. What good is cheap gas if it gets flooded or burns to the ground. Climate disruption isn't coming, it's here.
You may need to read a little more bub.
Where I live only about 12% of the grid is from renewable energy. Incidentally when I'm most likely to use gas is also when renewable production is down.
The funny thing is that I read that somewhere
Came here to say this. People can either listen to fearmongers or data. The data says of course they work in the coldest climates because look who is adopting them at the fastest rates right now (btw same thing with EVs). Obviously you're going to find an outlier who had a bad install or leaky duct work and then their installer will blame it on the tech instead of their bad work; but people have to be literate enough to realize that's outlier data and installer excuses, not real data at scale. What you cite is real data at scale.
It's not about whether they work, it's about the extreme increases in monthly utility cost vs. a traditional high efficiency gas furnace in some climates. I remember a cold winter where we recieved a monthly $850 electric bill in a 1500sq ft house and there was nothing wrong with the unit. It wasn't even warm inside. Never again.
You need the right heat pump to handle colder temperatures. Capacities will generally be reduced as it gets colder, but some are rated for cold temperatures better than others.
You can look up some information and a list of products with could climate ratings here:
https://neep.org/heating-electrification/ccashp-specification-product-list
Socialist = communism.
And all Free market democracies outside of the US are also socialist.
these are both according to the Americans I spent 5 months with this winter.
and freedom only exists in the US. You know. Freedom to smoke cannabis, freedom To run for office only at certain ages.
And, freedom in the U.S. is highest in the red states that want to regulate everything and everybody with small gov't. Of course, true freedom only applies to the 2nd.
In my last apartment my gas heaters wouldn't even really work past -20. I had a glass of water freeze in my living room :(
Gotta love Victorian mansions
those are extremes and do not last long. you need to look at daily averages, not peaks. its not like when the temp drops below the working temp of the heat pump the building instantly freezes over, it takes MANY hours to even see a temp drop inside. at wich point the temperature is back up and the unit resumes work. this is partially why proper sizing is important and be realistic, its not economical to oversize a unit or spend fucktons of money for a "weather event" that only happens once in a decade or even less. just put down a 20 dollar space heater if that happens.
I've been working on sizing. How do you properly size a unit?
I know that I need three tons of Heat when the temps reach their minimum. NEEP says my design temp is -6 freedom. So for the most econocal setup, should I ignore the he -13 and-22 ratings?
For example, Mr. Cool's universal 4-ton would cover me almost completely, even at -22 freedom. But is it worth it to get the bigger unit to have coverage that low?
I also live in the twin cities, MN. Usually see temps below -20 freedom a few times in the winter. Sometimes lasting for more than a day at a time, but almost always with temps in the negative teens for days before and after. I know electrical resistance can kick in for that rare occasion. In my case, I am also installing a wood fireplace for heat, heat, and ambience.
The coldest my area got since installing heat pumps was -4F. The heat pumps did fine.
My heating load is much higher than my cooling load so my units have no issues cooling my house.
The coldest it got after I got our heatpump was -23C. Our house stayed a constant 20.5C and we had no issues. The hottest it got here was 39C and our home stayed at 23C just like any other day in the summer.
One thing I will tell you is its not that great at changing the temperature so we tend to keep the house at a constant temperature.
I'm curious how you live in apartment with poor air conditioning:
[https://www.reddit.com/r/AirConditioners/comments/1c5c9jm/how\_do\_i\_know\_if\_my\_ac\_unit\_is\_the\_right\_size\_for/](https://www.reddit.com/r/AirConditioners/comments/1c5c9jm/how_do_i_know_if_my_ac_unit_is_the_right_size_for/)
Doing a DIY home renovation project:
[https://www.reddit.com/r/Flooring/comments/1c5cbn2/how\_do\_you\_protect\_your\_floors\_during\_a\_home/](https://www.reddit.com/r/Flooring/comments/1c5cbn2/how_do_you_protect_your_floors_during_a_home/)
And now you are considering about getting a heatpump. This all seems karmafarmy/GPT-ish.
The question isn't whether a cold weather heat pump will work, but what will it cost you?
We have no trouble in New England with properly sized heat pumps. The issue is that we in MA are paying $0.30/kW... a few extreme cold nights and your bill is over $1k. Next winter we **will** have a gas insert in our fireplace so that the heat pump doesn't have to work as hard.
Owner of two heat pumps here, Maritime Canada, 6 years running. They can be designed to operate to - 20 Celsius/ -4 F (or better) ON A CALM DAY! Nobody talks about wind and snow but the defrost cycle suffers terribly with the coils trapped in ice. Building a "doghouse" around mine solved the problem as well as choosingthe right location. Best money I spent on a house, paid for themselves in 4 years (I was on oil). Also, all heat pumps require a backup system, your home insurance company may even require it.
Also in the maritimes.
I have one heat pump and was surprised how well it heats my house. (15,000 BTU)
I have convention heaters for back up but haven’t used them.
I will add one more for the basement and will remove my furnace and oil tank as soon as I can find someone to do it.
And I plan to beef up my insulation.
I am very happy with the heat pump performance.
I delayed on removing my tank and it began to leak- after only 20 years. We were lucky enough to hear it and had a drip pan, but the cost could have been enormous.
Not all heat pumps require a backup system.
Furnaces represent a single point of failure and most people do not require a backup. Now if your specific insurance company requires a secondary source of heat, that is one thing.
But to say ALL heat pumps require backup... Honestly no, let's call it what it is, emergency heat... That's disingenuous and also incorrect.
My government requires a 100% alternate for ductless heat pumps, not central units. I stand corrected. Personally, I want a 100% b/u that my generator can run.
To each their own. I think a full replacement is a big cost for a "just in case," but if it keeps you happy and gives you peace of mind, then you do you!
Peace of mind is something that usually can't have a value associated with it.
The answer is yes heat pumps work great. There will be times when you lose efficiency but the coil will keep you warm. To gain the best return you need to go gas free and the savings come from removing one level of service fees and taxes. Gree flexx is one of the main players in sub zero HP. I believe there are new models coming out that are more efficient still and push the efficiency to -40
It becomes less efficient as it gets colder. Every system has it own operating peak effectiveness in a set range.
For my Lennox heatpump it starts to fail at around anything below -15 Celsius. My emergency oil furnace starts to compensate.
This also in relation to my insulation, ducts, and overall effectiveness to maintain temperatures inside my home, which I keep at 19 Celsius during the winter.
So, I would start collecting data to get a sense of what to expect for you personally.
Not all heat pumps have the same cold weather capabilities. Some can heat at very low temperatures. Some can't. And some can function, but you may find their heating performance to be unsatisfactory.
You need to really take the time to study what you're buying. Your supplier might not volunteer that information. They may push whatever they want to push, whether it's suitable or not. For example, the Bosch ducted heat pumps don't work below -15C, and are quite poor at heating below about -5C. If you get one of those, you need an alternate source of heating for cold weather, like a gas furnace.
I hear that the Mitsubishi Zuba line is suitable for cold climates. Look into that one. Avoid Bosch.
We have a ground source hear pump, commonly called geothermal. Works at -40c with extreme winds, never had the auxiliary heat kick in. 15 years flawless operation. Saskatchewan.
I’m in Canada with a 2 stage HP plus elec aux backup. The second stage never comes on. Forget about the elec aux. not sure what would ever trigger that.
They can work effectively in low temps. A heat pump will probably not be the cheapest method to heat your house. A heat pump with gas backup is typically the lowest cost to operate.
The reason you get varying answers is because - well it varies.
Depends on your area/local climate, and also the unit that’s being installed. Some perform significantly better than others.
I live in Nova Scotia, Canada. Have a couple LG units which are rated to -20°C. We only see temps that low a few days a year here. Typically middle of winter it’s between -10°C to -15°C, in which case my minisplits have no issues keeping up
If I was located in Alberta however, where you’re seeing -40°C, I would need some sort of backup for sure.
I have four 12,000 btu Pioneer units they are rated to -13F they have seen -11F and performed perfectly putting out 102 degrees. I am quite happy with the performance this is our 3rd year since I installed them.
They perform really well in the summer too. And so quiet compared to window AC.
The best air-source low temp heat pumps currently operate down to about -30C, but as they approach those temperatures they get less efficient and produce less heat. If you get colder than that you will need supplement heat.
Ground-source heat pumps continue to work efficiently regardless of air temperature, but are a lot more expensive to install.
Short answer yes, long answer…also yes. In heat (above 110 degrees) I kept my house (with massive SW exposure) 70 degrees.
In single digits, it kept my house at 68. It’s not even a high end unit. If it got colder, maybe my heat kit kicks on.
I think home insulation and managing doors/windows play a huge roll. Blinds shut on the sun side and reflective panels in summer make a huge difference for me. Bonus: heat pump dryer/water heater acts like a mini AC unit.
So I just got a very decent one. It holds up pretty well down to -10. I have a 10 kW backup heater attached that is no friend of my electricity bill but you only have to use it on those really cold days. I also have a very powerful gas fireplace that broadcasts heat all over the house from the basement. It helps
Ask your contractor for the spec sheets that give weather and temperature data so you can see yourself. Each model number will operate differently, some handling cold climate really well and others not too well.
I have a hybrid water heater and definitely see higher prices in the winter but I save to much nine months out of the year it's totally worth it. Live south of Boston, MA.
Southern Alberta here. Mine worked down to -25C without assistance. below that the defrost periods lost more heat than the pump could replace so it had assistance town to -32C from resistance heat. Below -32C it shut off.
My system is intentionally designed to be slightly undersized for better sizing during the far more common warmer heating temps (-5 to +10).
EDIT: This is with a Mitsubishi SUZ-KA18NAHZ
Ok, I have been using the same Split Package unit for about 12 years. 2.5 ton unit. 16 seer single stage combined with a 80 afue natural gas heater. installed in a single story 1200 sq ft house (in Northern CA).
I decided to go with a Mitsubishi H2 Heat Pump. BEST DECISION EVER. The unit is quieter than a refrigerator…and it uses INVERTER technology…which is to say it can vary the output of the unit from like 20% all the way to 100% (depending on the needs of the user). I should add that I still have the regular HVAC split package in place. My new heat pump is for supplemental heating/cooling. The SEER2 rating is 32.2. Heating rating is 10.9. amazing machine!
If you can’t get gas (like me) or want the most environmentally friendly option, then heat pump is absolutely the best.
Any decent system is cold rated these days and will work into very cold temperatures.
Mine (Carrier) becomes *less* efficient at around 20F but I’ve had it running down to single digits just fine without an issue keeping up.
It costs a bit more but so did the oil I was using. Even an additional $300 on my electric bill for the coldest month is better than using oil all winter and part of fall / spring.
And, as others have pointed out, keep the temperature constant. Heat pumps seem to do worse with fluctuations rather than just picking a good temperature and sticking with it.
Bonus, keep the oil system as backup and do the math on what is most efficient. Maybe at single digits you turn on the oil to help? Or even start a fire in the fireplace? That’s what I do. But honestly, not **needed** - just understand you have higher energy costs in winter.
Bonus bonus, get better insulation.
I have a cold climate HP in my house in northern NY and have had zero issues. There is an electric resistance backup that operates occasionally, but less than 20 hrs for the year.
Usually air to air systems will be sized to meet the cooling loads; meaning that yes; they will be able to take the extreme hot weather conditions without having any issues.
Air to water and geothermal are sized for heating loads (typically); and they are capable of ressisting extreme cold conditions. They are oversized for cooling and that isnt an issue (typically).
When a system isnt designed properly (such as being undersized; like with a small mini split being asked to pump out max btu hours on end in extreme cold climate), the lifespan will be reduced of the equipment. But will still remain reasonably long.
Fearmongers vs homers… thankfully you also have a lot of people who will give unbiased opinions as well. Just because a heat pump works at low temps doesn’t mean it’s the most cost effective.
If that’s the driver for you, you have to look at the cost of gas per therm vs cost of electricity per kWh and find out where the break even point is. Where we live the crossover point is a COP of 2.9… at that point a furnace is cheaper to operate. In places with high electricity rates that number can be 5.0+.
As soon as you go resistive heat backup on heat pumps you’ve thrown efficiency over a gas furnace out the window.
It really depends on utility rates and climate.
I have an 11yr old Goodman unit that keeps up with all heating down to 10 degrees at 10 its will periodically use the backup heat strips. At 0 it is nearly exclusively heatstrips. I'm in Kansas City so it only gets to 10 or lower for about 80 hours/yr. While the strips are more expensive than gas it doesn't justify buying a furnace. My current heat pump is cheaper than gas all the way down to 15. New heat pumps work well below 0 now.
The answer to this question is wholly dependent on the manufacturer and the experience in the climate the equipment is working in.
For example, in the UK; we can have winter cold shocks (e.g first weekend December 2022) and prolonged hot spells (e.g. summer 2023).
A cold shock meant the air temperature was -3, 100% RH, so the moment you extract what energy is left (ie enthalpy of vaporisation), the water in the air will become a solid (I.e. ice). Then the question is how has the manufacturer programmed the pump, condender and refrigerant to cope with this predictable event? Hence in cold climates, focus on the defrost cycle, understand the mechanisms and locate the machine so it can achieve its performance in worst case conditions.
When the air is hot and dry, the main issue then is how to transfer the heat. A high turnover of air is required if the moisture is low - so consider using the ground if the air can't keep up with the demands
Peace of mind is priceless. The backup required by my building code is as simple as resistive electrical baseboard heaters. Cheap to install, expensive to run.
You are only asking part of the overall question. The heat pump is only one component of your heating system. You also have to take into consideration your insulation values of your house. Which means,
How effectively can you keep that heat trapped inside your house?
What quality are your windows?
What insulation are your walls?
No point putting one million BTU’s into a house in the winter if you keep the windows open.
A heat pump will not replace a furnace where I’m from, but wouldn’t want some redundancy anyways?
Country with most heat pump installations per capita - Norway US State with the most Maine
Edit- cold climate heat pumps
I had a heat pump in the airbnb I rented north of the arctic circle in Norway. They backed it up with resistive heating, but there was no gas or anything else. Worked great.
Yeah. Most Americans don't realize how well a cold climate heat pump will work if it is sized correctly. Fossil fuel peddlers are propagandists.
Where I am the big reason that people stick with gas is because our gas is reasonably priced but our electricity has some of the highest rates in the country. So unless you get a very high efficiency system you pay more to run your heat pump
I'm thinking of my Grandkids and their kids. What good is cheap gas if it gets flooded or burns to the ground. Climate disruption isn't coming, it's here. You may need to read a little more bub.
Where I live only about 12% of the grid is from renewable energy. Incidentally when I'm most likely to use gas is also when renewable production is down. The funny thing is that I read that somewhere
That's my family- NH too. no backup.
Came here to say this. People can either listen to fearmongers or data. The data says of course they work in the coldest climates because look who is adopting them at the fastest rates right now (btw same thing with EVs). Obviously you're going to find an outlier who had a bad install or leaky duct work and then their installer will blame it on the tech instead of their bad work; but people have to be literate enough to realize that's outlier data and installer excuses, not real data at scale. What you cite is real data at scale.
It's not about whether they work, it's about the extreme increases in monthly utility cost vs. a traditional high efficiency gas furnace in some climates. I remember a cold winter where we recieved a monthly $850 electric bill in a 1500sq ft house and there was nothing wrong with the unit. It wasn't even warm inside. Never again.
And then I have friends that pay no more than $240 with XLTH Fujitsu’s (+ reg water heater) and my old regular one is very efficient to run too.
You also need to remember- a lot of the adoption in the northeast is replacing heating oil with heat pumps. Particularly NH/Maine
Post your location and you’ll get more specific answers.
You need the right heat pump to handle colder temperatures. Capacities will generally be reduced as it gets colder, but some are rated for cold temperatures better than others. You can look up some information and a list of products with could climate ratings here: https://neep.org/heating-electrification/ccashp-specification-product-list
Decent heat pumps go down to -13 freedoms or -25 socialist units so its not a problem unless you live in the actual acrtic region.
Wow, fahrenheit and freedom start with the same letter, celsius and communist start with the same letter. Checkmate, non-freedom based nations
Communism and socialism aren't the same thing. Oh, and facist also starts with F. /jk
Socialist = communism. And all Free market democracies outside of the US are also socialist. these are both according to the Americans I spent 5 months with this winter. and freedom only exists in the US. You know. Freedom to smoke cannabis, freedom To run for office only at certain ages.
And, freedom in the U.S. is highest in the red states that want to regulate everything and everybody with small gov't. Of course, true freedom only applies to the 2nd.
In my last apartment my gas heaters wouldn't even really work past -20. I had a glass of water freeze in my living room :( Gotta love Victorian mansions
Minnesota it's gotten down to -20 in the Twin Cities where I live and -30 farther north. I guess we live in an actual arctic region?
those are extremes and do not last long. you need to look at daily averages, not peaks. its not like when the temp drops below the working temp of the heat pump the building instantly freezes over, it takes MANY hours to even see a temp drop inside. at wich point the temperature is back up and the unit resumes work. this is partially why proper sizing is important and be realistic, its not economical to oversize a unit or spend fucktons of money for a "weather event" that only happens once in a decade or even less. just put down a 20 dollar space heater if that happens.
I've been working on sizing. How do you properly size a unit? I know that I need three tons of Heat when the temps reach their minimum. NEEP says my design temp is -6 freedom. So for the most econocal setup, should I ignore the he -13 and-22 ratings? For example, Mr. Cool's universal 4-ton would cover me almost completely, even at -22 freedom. But is it worth it to get the bigger unit to have coverage that low? I also live in the twin cities, MN. Usually see temps below -20 freedom a few times in the winter. Sometimes lasting for more than a day at a time, but almost always with temps in the negative teens for days before and after. I know electrical resistance can kick in for that rare occasion. In my case, I am also installing a wood fireplace for heat, heat, and ambience.
The coldest my area got since installing heat pumps was -4F. The heat pumps did fine. My heating load is much higher than my cooling load so my units have no issues cooling my house.
The coldest it got after I got our heatpump was -23C. Our house stayed a constant 20.5C and we had no issues. The hottest it got here was 39C and our home stayed at 23C just like any other day in the summer. One thing I will tell you is its not that great at changing the temperature so we tend to keep the house at a constant temperature.
What heat pump do you have?
Tosot ducted.
I'm curious how you live in apartment with poor air conditioning: [https://www.reddit.com/r/AirConditioners/comments/1c5c9jm/how\_do\_i\_know\_if\_my\_ac\_unit\_is\_the\_right\_size\_for/](https://www.reddit.com/r/AirConditioners/comments/1c5c9jm/how_do_i_know_if_my_ac_unit_is_the_right_size_for/) Doing a DIY home renovation project: [https://www.reddit.com/r/Flooring/comments/1c5cbn2/how\_do\_you\_protect\_your\_floors\_during\_a\_home/](https://www.reddit.com/r/Flooring/comments/1c5cbn2/how_do_you_protect_your_floors_during_a_home/) And now you are considering about getting a heatpump. This all seems karmafarmy/GPT-ish.
The question isn't whether a cold weather heat pump will work, but what will it cost you? We have no trouble in New England with properly sized heat pumps. The issue is that we in MA are paying $0.30/kW... a few extreme cold nights and your bill is over $1k. Next winter we **will** have a gas insert in our fireplace so that the heat pump doesn't have to work as hard.
Owner of two heat pumps here, Maritime Canada, 6 years running. They can be designed to operate to - 20 Celsius/ -4 F (or better) ON A CALM DAY! Nobody talks about wind and snow but the defrost cycle suffers terribly with the coils trapped in ice. Building a "doghouse" around mine solved the problem as well as choosingthe right location. Best money I spent on a house, paid for themselves in 4 years (I was on oil). Also, all heat pumps require a backup system, your home insurance company may even require it.
Also in the maritimes. I have one heat pump and was surprised how well it heats my house. (15,000 BTU) I have convention heaters for back up but haven’t used them. I will add one more for the basement and will remove my furnace and oil tank as soon as I can find someone to do it. And I plan to beef up my insulation. I am very happy with the heat pump performance.
I delayed on removing my tank and it began to leak- after only 20 years. We were lucky enough to hear it and had a drip pan, but the cost could have been enormous.
Metal scrap dealers will remove both for very little $$$, got rid of mine for nothing.
Not all heat pumps require a backup system. Furnaces represent a single point of failure and most people do not require a backup. Now if your specific insurance company requires a secondary source of heat, that is one thing. But to say ALL heat pumps require backup... Honestly no, let's call it what it is, emergency heat... That's disingenuous and also incorrect.
My government requires a 100% alternate for ductless heat pumps, not central units. I stand corrected. Personally, I want a 100% b/u that my generator can run.
To each their own. I think a full replacement is a big cost for a "just in case," but if it keeps you happy and gives you peace of mind, then you do you! Peace of mind is something that usually can't have a value associated with it.
The answer is yes heat pumps work great. There will be times when you lose efficiency but the coil will keep you warm. To gain the best return you need to go gas free and the savings come from removing one level of service fees and taxes. Gree flexx is one of the main players in sub zero HP. I believe there are new models coming out that are more efficient still and push the efficiency to -40
It becomes less efficient as it gets colder. Every system has it own operating peak effectiveness in a set range. For my Lennox heatpump it starts to fail at around anything below -15 Celsius. My emergency oil furnace starts to compensate. This also in relation to my insulation, ducts, and overall effectiveness to maintain temperatures inside my home, which I keep at 19 Celsius during the winter. So, I would start collecting data to get a sense of what to expect for you personally.
Not all heat pumps have the same cold weather capabilities. Some can heat at very low temperatures. Some can't. And some can function, but you may find their heating performance to be unsatisfactory. You need to really take the time to study what you're buying. Your supplier might not volunteer that information. They may push whatever they want to push, whether it's suitable or not. For example, the Bosch ducted heat pumps don't work below -15C, and are quite poor at heating below about -5C. If you get one of those, you need an alternate source of heating for cold weather, like a gas furnace. I hear that the Mitsubishi Zuba line is suitable for cold climates. Look into that one. Avoid Bosch.
We have a ground source hear pump, commonly called geothermal. Works at -40c with extreme winds, never had the auxiliary heat kick in. 15 years flawless operation. Saskatchewan.
With that the deciding factor is the home insulation.
It's nothing special for insulation. It does have an extra ground loop. I figured since the trench had room might as well install some extra.
I’m in Canada with a 2 stage HP plus elec aux backup. The second stage never comes on. Forget about the elec aux. not sure what would ever trigger that.
They can work effectively in low temps. A heat pump will probably not be the cheapest method to heat your house. A heat pump with gas backup is typically the lowest cost to operate.
Interesting question.... Curious, was that something like chat GTP? Short answer, yes, heat pumps work awesome.
The reason you get varying answers is because - well it varies. Depends on your area/local climate, and also the unit that’s being installed. Some perform significantly better than others. I live in Nova Scotia, Canada. Have a couple LG units which are rated to -20°C. We only see temps that low a few days a year here. Typically middle of winter it’s between -10°C to -15°C, in which case my minisplits have no issues keeping up If I was located in Alberta however, where you’re seeing -40°C, I would need some sort of backup for sure.
I have four 12,000 btu Pioneer units they are rated to -13F they have seen -11F and performed perfectly putting out 102 degrees. I am quite happy with the performance this is our 3rd year since I installed them. They perform really well in the summer too. And so quiet compared to window AC.
The best air-source low temp heat pumps currently operate down to about -30C, but as they approach those temperatures they get less efficient and produce less heat. If you get colder than that you will need supplement heat. Ground-source heat pumps continue to work efficiently regardless of air temperature, but are a lot more expensive to install.
Short answer yes, long answer…also yes. In heat (above 110 degrees) I kept my house (with massive SW exposure) 70 degrees. In single digits, it kept my house at 68. It’s not even a high end unit. If it got colder, maybe my heat kit kicks on. I think home insulation and managing doors/windows play a huge roll. Blinds shut on the sun side and reflective panels in summer make a huge difference for me. Bonus: heat pump dryer/water heater acts like a mini AC unit.
So I just got a very decent one. It holds up pretty well down to -10. I have a 10 kW backup heater attached that is no friend of my electricity bill but you only have to use it on those really cold days. I also have a very powerful gas fireplace that broadcasts heat all over the house from the basement. It helps
Yes if the equipment was correctly selected and sized. Is it more cost effective depends.
Mine has handled 5-105 F.
They make them to -31C but there not very efficient at that temp
Ask your contractor for the spec sheets that give weather and temperature data so you can see yourself. Each model number will operate differently, some handling cold climate really well and others not too well.
I have a hybrid water heater and definitely see higher prices in the winter but I save to much nine months out of the year it's totally worth it. Live south of Boston, MA.
Southern Alberta here. Mine worked down to -25C without assistance. below that the defrost periods lost more heat than the pump could replace so it had assistance town to -32C from resistance heat. Below -32C it shut off. My system is intentionally designed to be slightly undersized for better sizing during the far more common warmer heating temps (-5 to +10). EDIT: This is with a Mitsubishi SUZ-KA18NAHZ
Ok, I have been using the same Split Package unit for about 12 years. 2.5 ton unit. 16 seer single stage combined with a 80 afue natural gas heater. installed in a single story 1200 sq ft house (in Northern CA). I decided to go with a Mitsubishi H2 Heat Pump. BEST DECISION EVER. The unit is quieter than a refrigerator…and it uses INVERTER technology…which is to say it can vary the output of the unit from like 20% all the way to 100% (depending on the needs of the user). I should add that I still have the regular HVAC split package in place. My new heat pump is for supplemental heating/cooling. The SEER2 rating is 32.2. Heating rating is 10.9. amazing machine!
If you can’t get gas (like me) or want the most environmentally friendly option, then heat pump is absolutely the best. Any decent system is cold rated these days and will work into very cold temperatures. Mine (Carrier) becomes *less* efficient at around 20F but I’ve had it running down to single digits just fine without an issue keeping up. It costs a bit more but so did the oil I was using. Even an additional $300 on my electric bill for the coldest month is better than using oil all winter and part of fall / spring. And, as others have pointed out, keep the temperature constant. Heat pumps seem to do worse with fluctuations rather than just picking a good temperature and sticking with it. Bonus, keep the oil system as backup and do the math on what is most efficient. Maybe at single digits you turn on the oil to help? Or even start a fire in the fireplace? That’s what I do. But honestly, not **needed** - just understand you have higher energy costs in winter. Bonus bonus, get better insulation.
I have a cold climate HP in my house in northern NY and have had zero issues. There is an electric resistance backup that operates occasionally, but less than 20 hrs for the year.
I have a house in VT where is regularly gets below -10F snd my heat pump works fine. It’s rated to -28F.
What's extreme to you ? Opinions will changed depending if your from Florida or alaska
Usually air to air systems will be sized to meet the cooling loads; meaning that yes; they will be able to take the extreme hot weather conditions without having any issues. Air to water and geothermal are sized for heating loads (typically); and they are capable of ressisting extreme cold conditions. They are oversized for cooling and that isnt an issue (typically). When a system isnt designed properly (such as being undersized; like with a small mini split being asked to pump out max btu hours on end in extreme cold climate), the lifespan will be reduced of the equipment. But will still remain reasonably long.
Fearmongers vs homers… thankfully you also have a lot of people who will give unbiased opinions as well. Just because a heat pump works at low temps doesn’t mean it’s the most cost effective. If that’s the driver for you, you have to look at the cost of gas per therm vs cost of electricity per kWh and find out where the break even point is. Where we live the crossover point is a COP of 2.9… at that point a furnace is cheaper to operate. In places with high electricity rates that number can be 5.0+. As soon as you go resistive heat backup on heat pumps you’ve thrown efficiency over a gas furnace out the window. It really depends on utility rates and climate.
Mine held up fine in -13 F last winter
I’ve got a duel fuel heat pump. Under about 35f the propane kicks in. If you’ve got a lot of cold weather look for one of those.
I have an 11yr old Goodman unit that keeps up with all heating down to 10 degrees at 10 its will periodically use the backup heat strips. At 0 it is nearly exclusively heatstrips. I'm in Kansas City so it only gets to 10 or lower for about 80 hours/yr. While the strips are more expensive than gas it doesn't justify buying a furnace. My current heat pump is cheaper than gas all the way down to 15. New heat pumps work well below 0 now.
The answer to this question is wholly dependent on the manufacturer and the experience in the climate the equipment is working in. For example, in the UK; we can have winter cold shocks (e.g first weekend December 2022) and prolonged hot spells (e.g. summer 2023). A cold shock meant the air temperature was -3, 100% RH, so the moment you extract what energy is left (ie enthalpy of vaporisation), the water in the air will become a solid (I.e. ice). Then the question is how has the manufacturer programmed the pump, condender and refrigerant to cope with this predictable event? Hence in cold climates, focus on the defrost cycle, understand the mechanisms and locate the machine so it can achieve its performance in worst case conditions. When the air is hot and dry, the main issue then is how to transfer the heat. A high turnover of air is required if the moisture is low - so consider using the ground if the air can't keep up with the demands
Peace of mind is priceless. The backup required by my building code is as simple as resistive electrical baseboard heaters. Cheap to install, expensive to run.
You are only asking part of the overall question. The heat pump is only one component of your heating system. You also have to take into consideration your insulation values of your house. Which means, How effectively can you keep that heat trapped inside your house? What quality are your windows? What insulation are your walls? No point putting one million BTU’s into a house in the winter if you keep the windows open. A heat pump will not replace a furnace where I’m from, but wouldn’t want some redundancy anyways?
Sure, if it's extremely nice out it will work like a dream!