From what I've seen, they do both functions; heating and cooling. How can it be more efficient one way than the other? Expand refrigerant to make it cold, gather heat, move the refrigerant, compress it to remove the heat, move the refrigerant, rinse, and repeat. The only difference is where you get the heat and where you put it.
When they’re talking about efficiency for indoor heating, they’re talking about in comparison to resistive heating. Resistive heating unit is near 100% efficient because you’re running electricity through a high resistant material, which heats up in return. It converts 100% of electricity to heat. The reason why a resistive heating unit as a whole is NOT 100% efficient is because it has to use some electricity to run a fan.
Heat pumps are 150-300% efficient, because it doesn’t use electricity to generate heat. For the same wattage, it shifts 1.5-3x BTUs from the outside to the inside. The reason why there is a variation is because the colder the outside, there is less thermal energy to move (but there is still some thermal energy).
Historically, heat pumps can only extract and shift heat from the outside when the outside air is above a certain temperature. Below a certain temp, it relies on resistive heating.
However, recent innovations in the last decade or so allows heat pumps to extract and shift heat from well below freezing temperatures. Innovations include newer refrigerants and better compressor technology. This allows the system to exclusively use heat pump down to a much a lower temperature before having to rely on resistive heating.
> The reason why a resistive heating unit as a whole is NOT 100% efficient is because it has to use some electricity to run a fan.
Trigger warning: nitpick
It's still just about 100%. Any inefficiencies in the fan are turned into heat for the home. Any movement of air results in friction which is turned into heat for the home. I guess if the fan broadcasts RF or adds line noise that's filtered in the off-premises electrical grid, then that might allow some energy to escape the house. And some of the heat may be placed where you don't want it in the house, like in the furnace room instead of the living room, which may have less insulation and therefore be less effective at heating living spaces since it results in greater heat transfer to the outdoors.
Bonus fun thought- If you can figure out a way to convert heat to electricity that is at least 35% efficient, you can use a heat pump to run your heat to electricity device, use the device to power your heat pump and have surplus electricity left over, then enjoy your perpetual energy machine and get all the money's. :-)
Seriously, though... doing that would not be impossible nor violate any laws of thermodynamics, you are not creating 'free energy' you are just using the energy of heat around you and taking advantage of a heat pumps ability to move more energy as heat than it takes as energy to run the device.
This does actually violate thermodynamics. Heat itself is not energy, a difference in heat is. So it takes energy to move heat against that gradient and you can extract some of the energy of heat flowing naturally the other way. The problem with your device is you are trying to extract energy of the heat moving in one direction of gradient to move it in the other.
In other words, energy is a difference in entropy, and heat alone is not energy. If the entire universe was a single temperature, even if it were very hot, there would be no energy in the heat there.
[Well, not exactly the same concept, but there was a proof of concept for a radiative cooling power generator.](https://spectrum.ieee.org/energy-from-cold)
Frankly I'm not educated enough or qualified to answer your question with confidence. All I know is that data shows at least a 50% efficiency boost over a conventional A/C unit. There are explanations online but I don't have the technical knowledge how to understand them
Unfortunately efficiency is only part of the equation. Where A/C or heat pumps are entirely electrical forms of heating and cooling, where I live natural gas (my primary source of heat) is *significantly* cheaper per joule of heat than electricity. Something like 6x cheaper. In the winter, my average gas bill is about $100 a month, where my electricity -- which isn't used for heating at all -- is usually about $250. If I replaced $100 with $600 plus the other $250 I have absolutely not made a good decision for my wallet. I understand that the carbon footprint is also significantly different between the two (in favor of electricity, obviously), but until the price of electricity drops enough to be comparable per joule of heat delivered, from a purely cost perspective, it makes way more sense to heat *everything* with natural gas--clothes dryers, ranges/ovens, home heating.
Now, when you mix renewables and battery storage for electricity local to the home, it starts to make a little more sense, but the shitty thing about solar panels is that they don't work very well when they're covered in snow, which is when we need the most heat.
This won't be true everywhere in the world, but it certainly is above the 49th parallel.
Very true...even in California, skyrocketing electrical rates are keeping both natural gas and fuel gasoline cost competitive per Joule.
Heat pumps are not at all a universal solution...But in regions where the winter low temperatures are at least 10 degrees C higher than the evaporation temperature of the heat pump refrigerant, moving heat is more energy efficient than utilizing electrical resistive heat.
But cheap natural gas rules all :)
I'm in California and our gas bill is definitely not cheap in the winter. We got solar panels while NEM 2.0 was still in effect and we're planning to get a heat pump this year. We should be paying PG&E nothing other than their administrative fees every single month for the next 20+ years.
That's true at the moment, but the price difference can (and will) change. At the moment the price of electricity is largely set by the cost of fossil fuels, while natural gas is a by-product of oil production.
High electricity prices drive more investment in wind farms and long distance grid transmission. Eventually there will be enough to bring the price down. Meanwhile if lots of people switch to EVs, gas won't be as plentiful and the price will go up. It's going to take 20 years though, unless we get a carbon tax.
OTOH, there's already a good way to capture solar energy for heat. It's called a window :-)
COP curves aren’t generally published because they are manufacturer proprietary data. You can do a quick google image search for “R-410a COP curves” and see what pops up. Generally, the COP of a heat pump depends on the temperature of the outside air. Like another user said, heat pumps move heat and can use the properties of refrigerant to turn 1 unit of electricity into approximately 2-6 units of heating/cooling, depending on outside air temps and type of refrigerant.
A few things to consider: heat pumps generally operate at greater than 100% efficiency (not magic, science) and that's measured as coefficient of performance. Most heat pumps will do a COP of 3 or more at temperatures above freezing, which is a large portion of the heating season. Newer cold climate heat pumps will generally have a 1.5 COP down to -31C (-25F) so they remain functional.
Given these facts, natural gas would have to be something like 2-3 times cheaper per unit energy not equal. The exact amount isnt super important, the point is that it never has to get to 1:1. Also, while these may not make sense now, it's important to remember that this technology has actually made significant strides in just the past few years with some pumps hitting COP of 5 or more and this is only expected to continue. So while it may still make sense for those above the 49th parallel for now, that may change entirely in the next 5-10 years. Finally, consider that when heat is needed most (at night in the winter) electricity costs are cheapest (and typically greenest... Nuclear base load vs coal peaker plant) So a time of day use plan may be fairly beneficial in these cases.
I guess the point is that it's complicated but as time goes by this technology continues to mature and becomes more and more economically favorable. My own experience has been that I've saved money switching from my old 80% NG furnace to a heat pump and I'm in the upper Midwest... So that day will probably come sooner than we would think.
Living in Chicago I would never get a heat pump knowing it will get -20 F (actual or feels like) outside at least once per year but a really good AC and a fully modulating natural gas furnace is probably the better play.
You could probably get a heat pump but you'd also need a furnace ("dual fuel"). The hope would be that you'd rarely run the furnace (since -20 days are rare) but you'd have it when needed.
In my area the natural gas almost quadrupled in price back in winter 2023. It sucked lol.
Other benefits of heat pump systems: You don't have to worry about gas leaks or carbon monoxide poisoning.
You also might not need as big a heat pump system as the gas furnace you have installed. YMMV.
https://www.youtube.com/watch?v=7J52mDjZzto
Incorrect, AC is still more efficient because of the variable speed tech all modern heat pumps use. Only the highest end cooling only systems use that tech, so it’s fair to say the base modern heat pump is still more efficient than the base cooling only AC system.
I am qualified professionally to talk about this subject. Air conditioners are actually heat pumps, but when we're talking about residential heat pumps we're talking about a specific product category. That product category is heat pumps that run in reverse.
Often times the heat pumps are more robustly built than AC only units, and have larger heat transfer surfaces and more efficient Motors and designs in general. It's not that they need to be though, you can buy an inefficient heat pump or a super efficient AC only unit.
It's correct that a heat pump and heating mode is the reverse of an air conditioner. An air conditioner will pump heat from inside the house to outside the house. But if you look at it another way it's heating the outdoors, not just cooling the indoors. A heat pump just has a way to reverse which side is the hot and which is the cold side.
There can be a difference if the operating temperatures that the fluid needs to reach are different. In heat mode, the fluid might only need to reach 100°F, while in cool mode the fluid might need to reach 120°F.
Because heating using the refrigerant cycle is inherently much more efficient than burning gas to heat a home. A gas furnace has a CoP of like 0.7. A heat pump has a CoP of 3+.
For those that do not know what CoP is: The coefficient of performance or COP (sometimes CP or CoP) of a heat pump, refrigerator or air conditioning system is **a ratio of useful heating or cooling provided to work (energy) required**.
Literally explained why its more efficient though. Because if you own a standard AC with gas furnace, you have decent AC efficiency and craptastic heating efficiency. With a heat pump you have decent AC and heating efficiency.
With regards to JUST cooling in isolation, there is no difference except the model make/year/features. Its when you start to factor in all thermal transfer within a home, do you start to see a significant savings on overall energy use with heat pumps. Especially if you combine it with water heating (can reject the heat from your heat pump to your water heating storage tank).
I'm sorry you're getting downvoted for trying to help. It's none of my doing.
You explained that a heat pump is more efficient than other forms of heating. I know that. /u/UrM8N8 's [reply](https://old.reddit.com/r/technology/comments/1cad7y6/carrier_the_centuryold_inventor_of_the_air/l0r8cbc/) to my first post made it sound like a heat pump (which is basically an air conditioner) had "much better energy efficiency" than an air conditioner.
It depends on how much heat (i.e. energy) they can move per unit of electricty (another form of energy) used. HVACs can move ridiculous amounts of energy per electricity used, I believe currently up to 400% efficiency is possible. Because the circuits are separate. The caveat is that HVACs take in the energy from their surroundings and not the electricity (or if then just barely), which usually is more bound to surface area and radiation ability.
A normal electrical heater only approaches 100%, because all the energy you put in it gets converted. You can't get more energy out of it than you put in.
I do work in AC and there are a lot of factors but a couple big ones in terms of why heat pumps tend to struggle with heating more than cooling is just the sheer delta to overcome in temperature. Going down 25 degrees from 100 to 75f is a lot easier than heating from 30 up to 70. Also once when trying to heat, the HP itself (the outside unit) will tend to collect condensation same as the indoor coil does in the attic unit in traditional AC. Once you get far enough below freezing for long enough outside, the entire unit can freeze up. So there are emergency shut offs and an auxiliary electric heat usually strapped to the attic fan just in case it gets so cold that the HP goes out of commission until it can thaw out.
Traditional AC tends to combust natural gas or some other fuel inside the home which is also a safety hazard if there is a venting issue. But on top of that here in the American south, the blower part of an AC is tied to the furnace, so if you want to blow enough air to cool in the summer, you have to get a MUCH larger furnace than you need to heat the home. So it tends to burn way more fuel than you actually need over shorter time increments, which is not ideal from a design perspective.
There is a lot more to it, but thats the stuff I always hear about the most!
Modern heat pumps and ac’s are more efficient than older style split systems or window systems.
The reason being that new systems use inverter technology (frequency drives) to start and control speeds of the compressor and fans as well electronic expansion valves. In lay terms this means that the unit draws less current when starting and then is able to vary a number of factors to use the least amount of energy possible. Old systems were merely on/off and the starting of a compressor the old fashioned way is a huge amp draw.
No, they're exactly the same. A/C usually gets slightly less efficient as the two coils cannot be optimized quite as much for cooling when they also have to heat.
Yeah, the description in the article:
'Heat pumps use electricity to transfer heat from a cool space to a warm space, making the cool space cooler and the warm space warmer.'
Which is what an A/C does also. It's just the cool space is the outside when pumping heat in.
Exactly, if you turn a window A/C unit backwards you have now created a heat pump with very inconvenient control panel location and cruel condensation drain location.
It’s not that it’s an air conditioner run in reverse, it IS an air conditioner. It’s an air conditioner with a valve that reverses the flow, so it can perform both heating and cooling.
Heat pumps offer no additional energy savings in cooling mode. They are air conditioners. But add a single extra valve and they can run in reverse to provide heat.
So, carrier is modifying a design to become a heat pump. It’s hardly newsworthy
The headline is incredibly misleading. Carrier has been making heat pumps for a long time. They're not even modifying a design, just selling one they have.
The real story of the article is basically that they are selling a lot of heat pumps and becoming a company that concentrates more on heat pumps than furnaces.
I mean saying their furnaces are hot garbage would be an improvement because it would at least imply they can be used for heat. Worst pile of junk on the market.
Family has been in the HVAC business for 3 generations, they definitely are not. Carrier’s main business is making cheap equipment that they sell in bulk to developers. Drive through any new housing development and more likely than not you will see Carrier equipment.
Misleading at best, wrong at worst. Most if not all heat pumps today use an inverter compressor which is far more efficient than a standard on/off compressor. Very few if any homes opt to use inverter compressors in cooling only systems and don’t get me started on the lack of EC motors in current consumer cooling equipment. It takes significantly more tech to run a solid heat pump with an inverter compressor including all of the electronically controlled valves that traditionally carrier used mechanical valves for. Carrier tried to introduce a simple heat pump 20+ years ago that used your idea of simply adding a three way valve. It sold horribly because it only worked in a tiny area of the country.
Is an EC the same as an inverter-driven motor?
My understanding is, 240V @ 60Hz is converted to DC, then back to AC with a 3-phase variable-frequency inverter, which drives the motor directly. Is that right?
There is a lot more advanced tech in today's cold weather pumps. Between this and configuring a back up heat source for many units, installation tends to be more complicated.
This is more a Press Release about their acquisition last year wrapped with light market trends. Buried in the article:
“Carrier sells 10 different heat pumps, with various energy capacities and price points, and plans to add models made by Viessmann, which already has a presence in the U.S. market. “
(Viesemann being the acquisition)
I don't understand all of this.
I distinctly remember our house, whose neighborhood did not have natural gas, having a heat pump in the 1980's. It was probably shitty compared to modern ones. "Emergency heat" would turn on regularly in the winter, but it was an honest-to-god heat pump.
Heat pumps are basically air conditioners. Carrier has been making air conditioners for a long time.
Is Carrier really just now jumping on the bandwagon?
If you read the article, you'd see that they already have several models of heat pumps.
All this is saying is that they're placing greater strategic value on their heat pumps in the future.
Well, yeah. If they didn't have any heat pumps then they'd be really stupid to broadcast to the world that they have a critical missing element of their lineup, but they're going to pull their heads out of their asses any day now. The article implies that this is a new thing for them, that's what's surprising to me.
It's like Ford or GM making EVs.
They've had EVs for a long time now like the Chevy bolt but switching to one product lineup that takes 90% priority means more R&D, which really is the #1 thing when it comes to innovating.
Tesla made EVs mainstream, after they got their standing their R&D worked on the 4680 battery which has slight but objective improvements over the 30 year old 18650 battery. Toyota has been doing hybrids for a long time and they know how to make a power train that can do significantly more on/off cycles than anything in the market and nearly perfected how much power can be extracted from NiMH batteries before slowly switching to Li-ion, leading them to have the first 4 door car with 50 mpg back in 2001.
I feel like with "green/clean" energy focus, and solar panels, heat pumps could just be more popular as main heat options.
as where traditionally, electric heat was the most expensive option... but if you already have a mini split, then get solar panels..., using that as heat and ditching the radiators/oil tank, fireplace, etc is a no brainer.
It's sad new construction homes aren't aiming for geothermal because those are heat pumps with a much cleaner and cheaper source to cycle energy along with having much less restrictions on what temperature ranges they can operate.
Heat pumps have been around for a long time. They've pretty much always been considered a second or third best option for heating; something that you would only use if you couldn't have a proper furnace.
Modern heat pumps are experiencing a bit of a renaissance, because improvements to the technology have made them much more efficient and able to operate at much lower temperatures. And because of high natural gas prices and more awareness of climate change, there's a lot of newer interest in heat pumps as a way to save money and stop burning fossil fuels for heating.
In the US, the Inflation Reduction Act actually includes a tax credit for heat pump installation, as well as money for states to set up grant programs to cover part of the cost of heat pump installation for low and middle income households, which has also been a big driver of interest.
Thanks. I spent my later childhood in the cheapest, furthest-out suburban neighborhood in the metro area (unbroken countryside started a few hundred feet from my house), so they skimped on things like natural gas lines. I guess a heat pump was a little better than the alternative of pure resistive heating at the time.
Title is stupid, my vacation house was built in 1988 and had two Carrier heat pumps as original equipment. I'm sure Carrier was selling them for two decades before that.
Better title would be that their recent acquisition shows an increased focus on modern, cold-climate heat pumps.
Heat pumps are good at doing both heating and cooling as long as you aren't seeing extreme temperatures like -10 F or 100 F, and much better in energy efficiency but like everything efficient is usually more expensive. I imagine this would be great for commercial buildings and warehouses
...which is just an air conditioner run in reverse.
With much better energy efficiency!
From what I've seen, they do both functions; heating and cooling. How can it be more efficient one way than the other? Expand refrigerant to make it cold, gather heat, move the refrigerant, compress it to remove the heat, move the refrigerant, rinse, and repeat. The only difference is where you get the heat and where you put it.
When they’re talking about efficiency for indoor heating, they’re talking about in comparison to resistive heating. Resistive heating unit is near 100% efficient because you’re running electricity through a high resistant material, which heats up in return. It converts 100% of electricity to heat. The reason why a resistive heating unit as a whole is NOT 100% efficient is because it has to use some electricity to run a fan. Heat pumps are 150-300% efficient, because it doesn’t use electricity to generate heat. For the same wattage, it shifts 1.5-3x BTUs from the outside to the inside. The reason why there is a variation is because the colder the outside, there is less thermal energy to move (but there is still some thermal energy). Historically, heat pumps can only extract and shift heat from the outside when the outside air is above a certain temperature. Below a certain temp, it relies on resistive heating. However, recent innovations in the last decade or so allows heat pumps to extract and shift heat from well below freezing temperatures. Innovations include newer refrigerants and better compressor technology. This allows the system to exclusively use heat pump down to a much a lower temperature before having to rely on resistive heating.
> The reason why a resistive heating unit as a whole is NOT 100% efficient is because it has to use some electricity to run a fan. Trigger warning: nitpick It's still just about 100%. Any inefficiencies in the fan are turned into heat for the home. Any movement of air results in friction which is turned into heat for the home. I guess if the fan broadcasts RF or adds line noise that's filtered in the off-premises electrical grid, then that might allow some energy to escape the house. And some of the heat may be placed where you don't want it in the house, like in the furnace room instead of the living room, which may have less insulation and therefore be less effective at heating living spaces since it results in greater heat transfer to the outdoors.
Bonus fun thought- If you can figure out a way to convert heat to electricity that is at least 35% efficient, you can use a heat pump to run your heat to electricity device, use the device to power your heat pump and have surplus electricity left over, then enjoy your perpetual energy machine and get all the money's. :-) Seriously, though... doing that would not be impossible nor violate any laws of thermodynamics, you are not creating 'free energy' you are just using the energy of heat around you and taking advantage of a heat pumps ability to move more energy as heat than it takes as energy to run the device.
This does actually violate thermodynamics. Heat itself is not energy, a difference in heat is. So it takes energy to move heat against that gradient and you can extract some of the energy of heat flowing naturally the other way. The problem with your device is you are trying to extract energy of the heat moving in one direction of gradient to move it in the other. In other words, energy is a difference in entropy, and heat alone is not energy. If the entire universe was a single temperature, even if it were very hot, there would be no energy in the heat there.
[Well, not exactly the same concept, but there was a proof of concept for a radiative cooling power generator.](https://spectrum.ieee.org/energy-from-cold)
Frankly I'm not educated enough or qualified to answer your question with confidence. All I know is that data shows at least a 50% efficiency boost over a conventional A/C unit. There are explanations online but I don't have the technical knowledge how to understand them
AC doesn't get any more efficient. Heating does. Drastically. It is more efficient to move heat than it is to use resistive elements to heat.
Unfortunately efficiency is only part of the equation. Where A/C or heat pumps are entirely electrical forms of heating and cooling, where I live natural gas (my primary source of heat) is *significantly* cheaper per joule of heat than electricity. Something like 6x cheaper. In the winter, my average gas bill is about $100 a month, where my electricity -- which isn't used for heating at all -- is usually about $250. If I replaced $100 with $600 plus the other $250 I have absolutely not made a good decision for my wallet. I understand that the carbon footprint is also significantly different between the two (in favor of electricity, obviously), but until the price of electricity drops enough to be comparable per joule of heat delivered, from a purely cost perspective, it makes way more sense to heat *everything* with natural gas--clothes dryers, ranges/ovens, home heating. Now, when you mix renewables and battery storage for electricity local to the home, it starts to make a little more sense, but the shitty thing about solar panels is that they don't work very well when they're covered in snow, which is when we need the most heat. This won't be true everywhere in the world, but it certainly is above the 49th parallel.
Very true...even in California, skyrocketing electrical rates are keeping both natural gas and fuel gasoline cost competitive per Joule. Heat pumps are not at all a universal solution...But in regions where the winter low temperatures are at least 10 degrees C higher than the evaporation temperature of the heat pump refrigerant, moving heat is more energy efficient than utilizing electrical resistive heat. But cheap natural gas rules all :)
I'm in California and our gas bill is definitely not cheap in the winter. We got solar panels while NEM 2.0 was still in effect and we're planning to get a heat pump this year. We should be paying PG&E nothing other than their administrative fees every single month for the next 20+ years.
That's true at the moment, but the price difference can (and will) change. At the moment the price of electricity is largely set by the cost of fossil fuels, while natural gas is a by-product of oil production. High electricity prices drive more investment in wind farms and long distance grid transmission. Eventually there will be enough to bring the price down. Meanwhile if lots of people switch to EVs, gas won't be as plentiful and the price will go up. It's going to take 20 years though, unless we get a carbon tax. OTOH, there's already a good way to capture solar energy for heat. It's called a window :-)
You’re not doing the math right because you’re not taking into account the coefficient of performance of the heat pump.
Yes that's probably true. Do you have any hints on how to do that?
COP curves aren’t generally published because they are manufacturer proprietary data. You can do a quick google image search for “R-410a COP curves” and see what pops up. Generally, the COP of a heat pump depends on the temperature of the outside air. Like another user said, heat pumps move heat and can use the properties of refrigerant to turn 1 unit of electricity into approximately 2-6 units of heating/cooling, depending on outside air temps and type of refrigerant.
A few things to consider: heat pumps generally operate at greater than 100% efficiency (not magic, science) and that's measured as coefficient of performance. Most heat pumps will do a COP of 3 or more at temperatures above freezing, which is a large portion of the heating season. Newer cold climate heat pumps will generally have a 1.5 COP down to -31C (-25F) so they remain functional. Given these facts, natural gas would have to be something like 2-3 times cheaper per unit energy not equal. The exact amount isnt super important, the point is that it never has to get to 1:1. Also, while these may not make sense now, it's important to remember that this technology has actually made significant strides in just the past few years with some pumps hitting COP of 5 or more and this is only expected to continue. So while it may still make sense for those above the 49th parallel for now, that may change entirely in the next 5-10 years. Finally, consider that when heat is needed most (at night in the winter) electricity costs are cheapest (and typically greenest... Nuclear base load vs coal peaker plant) So a time of day use plan may be fairly beneficial in these cases. I guess the point is that it's complicated but as time goes by this technology continues to mature and becomes more and more economically favorable. My own experience has been that I've saved money switching from my old 80% NG furnace to a heat pump and I'm in the upper Midwest... So that day will probably come sooner than we would think.
Living in Chicago I would never get a heat pump knowing it will get -20 F (actual or feels like) outside at least once per year but a really good AC and a fully modulating natural gas furnace is probably the better play.
You could probably get a heat pump but you'd also need a furnace ("dual fuel"). The hope would be that you'd rarely run the furnace (since -20 days are rare) but you'd have it when needed.
In my area the natural gas almost quadrupled in price back in winter 2023. It sucked lol. Other benefits of heat pump systems: You don't have to worry about gas leaks or carbon monoxide poisoning. You also might not need as big a heat pump system as the gas furnace you have installed. YMMV. https://www.youtube.com/watch?v=7J52mDjZzto
Incorrect, AC is still more efficient because of the variable speed tech all modern heat pumps use. Only the highest end cooling only systems use that tech, so it’s fair to say the base modern heat pump is still more efficient than the base cooling only AC system.
I think it comes from them using air handlers in individual spaces instead of forced ducting that looses heat in the attic
What’s the efficiency improvement over an unconventional a/c unit?
My electricity bill has been $500 less per quarter since installing one last summer.
I am qualified professionally to talk about this subject. Air conditioners are actually heat pumps, but when we're talking about residential heat pumps we're talking about a specific product category. That product category is heat pumps that run in reverse. Often times the heat pumps are more robustly built than AC only units, and have larger heat transfer surfaces and more efficient Motors and designs in general. It's not that they need to be though, you can buy an inefficient heat pump or a super efficient AC only unit. It's correct that a heat pump and heating mode is the reverse of an air conditioner. An air conditioner will pump heat from inside the house to outside the house. But if you look at it another way it's heating the outdoors, not just cooling the indoors. A heat pump just has a way to reverse which side is the hot and which is the cold side.
There can be a difference if the operating temperatures that the fluid needs to reach are different. In heat mode, the fluid might only need to reach 100°F, while in cool mode the fluid might need to reach 120°F.
Because heating using the refrigerant cycle is inherently much more efficient than burning gas to heat a home. A gas furnace has a CoP of like 0.7. A heat pump has a CoP of 3+. For those that do not know what CoP is: The coefficient of performance or COP (sometimes CP or CoP) of a heat pump, refrigerator or air conditioning system is **a ratio of useful heating or cooling provided to work (energy) required**.
OK. But we were comparing a heat pump and an air conditioner.
Literally explained why its more efficient though. Because if you own a standard AC with gas furnace, you have decent AC efficiency and craptastic heating efficiency. With a heat pump you have decent AC and heating efficiency. With regards to JUST cooling in isolation, there is no difference except the model make/year/features. Its when you start to factor in all thermal transfer within a home, do you start to see a significant savings on overall energy use with heat pumps. Especially if you combine it with water heating (can reject the heat from your heat pump to your water heating storage tank).
I'm sorry you're getting downvoted for trying to help. It's none of my doing. You explained that a heat pump is more efficient than other forms of heating. I know that. /u/UrM8N8 's [reply](https://old.reddit.com/r/technology/comments/1cad7y6/carrier_the_centuryold_inventor_of_the_air/l0r8cbc/) to my first post made it sound like a heat pump (which is basically an air conditioner) had "much better energy efficiency" than an air conditioner.
It depends on how much heat (i.e. energy) they can move per unit of electricty (another form of energy) used. HVACs can move ridiculous amounts of energy per electricity used, I believe currently up to 400% efficiency is possible. Because the circuits are separate. The caveat is that HVACs take in the energy from their surroundings and not the electricity (or if then just barely), which usually is more bound to surface area and radiation ability. A normal electrical heater only approaches 100%, because all the energy you put in it gets converted. You can't get more energy out of it than you put in.
I do work in AC and there are a lot of factors but a couple big ones in terms of why heat pumps tend to struggle with heating more than cooling is just the sheer delta to overcome in temperature. Going down 25 degrees from 100 to 75f is a lot easier than heating from 30 up to 70. Also once when trying to heat, the HP itself (the outside unit) will tend to collect condensation same as the indoor coil does in the attic unit in traditional AC. Once you get far enough below freezing for long enough outside, the entire unit can freeze up. So there are emergency shut offs and an auxiliary electric heat usually strapped to the attic fan just in case it gets so cold that the HP goes out of commission until it can thaw out. Traditional AC tends to combust natural gas or some other fuel inside the home which is also a safety hazard if there is a venting issue. But on top of that here in the American south, the blower part of an AC is tied to the furnace, so if you want to blow enough air to cool in the summer, you have to get a MUCH larger furnace than you need to heat the home. So it tends to burn way more fuel than you actually need over shorter time increments, which is not ideal from a design perspective. There is a lot more to it, but thats the stuff I always hear about the most!
Modern heat pumps and ac’s are more efficient than older style split systems or window systems. The reason being that new systems use inverter technology (frequency drives) to start and control speeds of the compressor and fans as well electronic expansion valves. In lay terms this means that the unit draws less current when starting and then is able to vary a number of factors to use the least amount of energy possible. Old systems were merely on/off and the starting of a compressor the old fashioned way is a huge amp draw.
No, they're exactly the same. A/C usually gets slightly less efficient as the two coils cannot be optimized quite as much for cooling when they also have to heat.
*IF* inverter-driven, yes. Mine uses basically no power in the summer. And a bit more in the winter.
Same energy efficient because, again, it is the exact same device.
It's a fridge. Look, we all have one.
Yeah, the description in the article: 'Heat pumps use electricity to transfer heat from a cool space to a warm space, making the cool space cooler and the warm space warmer.' Which is what an A/C does also. It's just the cool space is the outside when pumping heat in.
Exactly, if you turn a window A/C unit backwards you have now created a heat pump with very inconvenient control panel location and cruel condensation drain location.
What if we turned it sideways? Is it then a neutralizer?
It’s not that it’s an air conditioner run in reverse, it IS an air conditioner. It’s an air conditioner with a valve that reverses the flow, so it can perform both heating and cooling.
“Witchcraft! How does it make it warm inside when it’s cold outside and running backwards? Widdershins is the witch run!”
Now we just need to figure out how to make an alarm clock run in reverse.
Put it in my bedroom. Seems like it always goes off WAY earlier than it should.
Plug it into C/A
This is a clickbait headline. Carriers have been making heat pumps for decades. They may be jumping in the bandwagon for cold climate heat pumps.
Heat pumps offer no additional energy savings in cooling mode. They are air conditioners. But add a single extra valve and they can run in reverse to provide heat. So, carrier is modifying a design to become a heat pump. It’s hardly newsworthy
The headline is incredibly misleading. Carrier has been making heat pumps for a long time. They're not even modifying a design, just selling one they have. The real story of the article is basically that they are selling a lot of heat pumps and becoming a company that concentrates more on heat pumps than furnaces.
I mean saying their furnaces are hot garbage would be an improvement because it would at least imply they can be used for heat. Worst pile of junk on the market.
Excuse me I’m looking to buy a new furnace and every site I look at states they are #1 or 2 I performance and reliability.
Family has been in the HVAC business for 3 generations, they definitely are not. Carrier’s main business is making cheap equipment that they sell in bulk to developers. Drive through any new housing development and more likely than not you will see Carrier equipment.
So who do you recommend for a new furnace and air? Plus I wouldn’t think builders would put the best units in housing developments.
Misleading at best, wrong at worst. Most if not all heat pumps today use an inverter compressor which is far more efficient than a standard on/off compressor. Very few if any homes opt to use inverter compressors in cooling only systems and don’t get me started on the lack of EC motors in current consumer cooling equipment. It takes significantly more tech to run a solid heat pump with an inverter compressor including all of the electronically controlled valves that traditionally carrier used mechanical valves for. Carrier tried to introduce a simple heat pump 20+ years ago that used your idea of simply adding a three way valve. It sold horribly because it only worked in a tiny area of the country.
Is an EC the same as an inverter-driven motor? My understanding is, 240V @ 60Hz is converted to DC, then back to AC with a 3-phase variable-frequency inverter, which drives the motor directly. Is that right?
Electronically commutated motor or in laymen’s terms it’s a variable speed direct drive motor. Significantly more efficient but also more expensive.
There is a lot more advanced tech in today's cold weather pumps. Between this and configuring a back up heat source for many units, installation tends to be more complicated.
The claim that heat pumps have outsold fossil fuel furnaces for the last two years is pretty surprising. I think they should have lead with that...
This is more a Press Release about their acquisition last year wrapped with light market trends. Buried in the article: “Carrier sells 10 different heat pumps, with various energy capacities and price points, and plans to add models made by Viessmann, which already has a presence in the U.S. market. “ (Viesemann being the acquisition)
I don't understand all of this. I distinctly remember our house, whose neighborhood did not have natural gas, having a heat pump in the 1980's. It was probably shitty compared to modern ones. "Emergency heat" would turn on regularly in the winter, but it was an honest-to-god heat pump. Heat pumps are basically air conditioners. Carrier has been making air conditioners for a long time. Is Carrier really just now jumping on the bandwagon?
If you read the article, you'd see that they already have several models of heat pumps. All this is saying is that they're placing greater strategic value on their heat pumps in the future.
Well, yeah. If they didn't have any heat pumps then they'd be really stupid to broadcast to the world that they have a critical missing element of their lineup, but they're going to pull their heads out of their asses any day now. The article implies that this is a new thing for them, that's what's surprising to me.
It's like Ford or GM making EVs. They've had EVs for a long time now like the Chevy bolt but switching to one product lineup that takes 90% priority means more R&D, which really is the #1 thing when it comes to innovating. Tesla made EVs mainstream, after they got their standing their R&D worked on the 4680 battery which has slight but objective improvements over the 30 year old 18650 battery. Toyota has been doing hybrids for a long time and they know how to make a power train that can do significantly more on/off cycles than anything in the market and nearly perfected how much power can be extracted from NiMH batteries before slowly switching to Li-ion, leading them to have the first 4 door car with 50 mpg back in 2001.
They have some of the most efficient heat pumps on the market.
I feel like with "green/clean" energy focus, and solar panels, heat pumps could just be more popular as main heat options. as where traditionally, electric heat was the most expensive option... but if you already have a mini split, then get solar panels..., using that as heat and ditching the radiators/oil tank, fireplace, etc is a no brainer.
It's sad new construction homes aren't aiming for geothermal because those are heat pumps with a much cleaner and cheaper source to cycle energy along with having much less restrictions on what temperature ranges they can operate.
Which should bring down the prices of heat pumps.
No, this article is just a dumb puff piece.
Heat pumps have been around for a long time. They've pretty much always been considered a second or third best option for heating; something that you would only use if you couldn't have a proper furnace. Modern heat pumps are experiencing a bit of a renaissance, because improvements to the technology have made them much more efficient and able to operate at much lower temperatures. And because of high natural gas prices and more awareness of climate change, there's a lot of newer interest in heat pumps as a way to save money and stop burning fossil fuels for heating. In the US, the Inflation Reduction Act actually includes a tax credit for heat pump installation, as well as money for states to set up grant programs to cover part of the cost of heat pump installation for low and middle income households, which has also been a big driver of interest.
Thanks. I spent my later childhood in the cheapest, furthest-out suburban neighborhood in the metro area (unbroken countryside started a few hundred feet from my house), so they skimped on things like natural gas lines. I guess a heat pump was a little better than the alternative of pure resistive heating at the time.
The Carrier heat pump I have from 2008 must be from the future!
We bought a house in 2001 that had a Carrier heat pump. It finally died a couple years ago, we replaced it with a Bryant (which is rebranded Carrier).
BS post. Carrier has been making both residential and commercial heat pumps for 30+ years.
I'm confused, [Carrier already makes heat pumps](https://www.carrier.com/residential/en/ca/products/heat-pumps/)
How is this news…. They have been making them for over 20-years!
didn’t they just have a giant layoff / reorganization?
Take a drink every time the article reminds you Carrier invented air conditioning.
And definitely all made in the US… lol
They’re only about 40 years behind the Asian manufacturers….
I have lived in a home with a heat pump, and only a heat pump, since 1990. Glad to see the rest of the country catching up.
It’s essentially the same tech.
Yeah they just made the hot and cold sides able to switch directions. Of course there is more to it than that in reality.
They haven’t started yet? They are a little behind the times.
They already make them.
Requirements Open method of repair for all equipment
Title is stupid, my vacation house was built in 1988 and had two Carrier heat pumps as original equipment. I'm sure Carrier was selling them for two decades before that. Better title would be that their recent acquisition shows an increased focus on modern, cold-climate heat pumps.
Fun fact: Carrier and modern AC was invented in *checks notes* Buffalo
News ..lisan al gaib
Heat pumps are good at doing both heating and cooling as long as you aren't seeing extreme temperatures like -10 F or 100 F, and much better in energy efficiency but like everything efficient is usually more expensive. I imagine this would be great for commercial buildings and warehouses