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How a heat pump works

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Re: How a heat pump works

#91

Post by megaman821 »

oceanplexian wrote: post #85
wongarsu wrote: post #27

Earlier quoted context omitted.

For a long time the main problem of heat pumps was that while they are more efficient, a kilowatthour of gas or oil is much cheaper than a kilowatthour of electricity. But in the last two years natural gas prizes have gone crazy, removing that price disadvantage. Of course heat pumps emitting no particulates and being able to run on renewables are also good reasons, especially as the health impact of living in cities…

An overlooked benefit is that they actually improve comfort over a boiler in a dry climate, so if you live somewhere with low humidity they help keep the air less dry. They also give you heating and cooling.. for places that don’t have Air Conditioning it’s a worthwhile upgrade.

I assume in home that don't have ACs, that they also don't have ducts. Do these ductless homes filter their air, control home humidity, or bring in fresh air from outside?

Re: How a heat pump works

#92

Post by [deleted] »

boringg wrote: post #7

What is going on? Is there a global push to get everyone to switch to heat pumps. It seems that there is heat pump content everywhere. Clearly there is a push. I understand that its for climate benefits but it feels very coordinated. edit: didn't realize the attention I would get. Let me add someone answered my question -- a good product market fit and people talking is probably where the push came from. That said HV…

[deleted]

Re: How a heat pump works

#93

Post by sbradford26 »

asow92 wrote: post #73
prottog wrote: post #57

Earlier quoted context omitted.

In the Northeast with that much square footage, you would be better off with ground-source heat pumps (whether open or closed loop), rather than the normal air-source heat pumps.

I guess the concern I have with all this is that my current system works well, and I don't want to spend $10K+ unless it brings down my heating costs significantly. Could a ground-source heat pump system do that?

Ground source/geothermal would significantly reduce your heating costs but it would be significantly more than 10k. For that large of house something like 40k+ wouldn't be out of the question, with the largest expense being drilling.

I personally think geothermal is great, sadly New England's geography makes getting a ground loop installed more difficult. In the midwest lots of people would do a horizontal loop by trenching like 8 feet underground laying pipe in there. In many parts of new england that isn't really viable with all the rock so vertical drilling is used which is significantly more expensive.

Re: How a heat pump works

#94

Post by helen___keller »

fullstop wrote: post #48
helen___keller wrote: post #30

Earlier quoted context omitted.

I’ve been independently interested in heat pumps because I need to replace my old end-of-life system and I’ve been interested if a modern cold-weather mini split system is a better investment. There’s lots of conflicting info I’ve found on if heat pumps perform in freezing weather and at what kind of efficiency. I’m sure there’s others in my position.

Where do you live geographically? I'm in eastern Pennsylvania and have lived with a heat pump for 20+ years.

Massachusetts

Re: How a heat pump works

#95

Post by Thlom »

mytailorisrich wrote: post #77
wongarsu wrote: post #27

Earlier quoted context omitted.

For a long time the main problem of heat pumps was that while they are more efficient, a kilowatthour of gas or oil is much cheaper than a kilowatthour of electricity. But in the last two years natural gas prizes have gone crazy, removing that price disadvantage. Of course heat pumps emitting no particulates and being able to run on renewables are also good reasons, especially as the health impact of living in cities…

It's not directly related to the recent spike in prices, especially considering that a heat pump installation is very expensive in itself and potentially disruptive. Rather, it's a combination wanting to get to net zero, so no emissions, with the big problem of generating enough green electricity. A heat pump system has no emissions and consumes much less electricity than an electric boiler/electric heater.

I replaced my old air-to-air heat pump with a new one last year. Cost me in total around $3000-$4000. Might have been a bit more expensive if it was a completely new install depending on how it would be installed, but not too much more expensive. Might be more expensive in countries where you are using gas boilers as it sounds like your heating setup is much more complex than where I live.

Re: How a heat pump works

#96

Post by achenatx »

boringg wrote: post #7

What is going on? Is there a global push to get everyone to switch to heat pumps. It seems that there is heat pump content everywhere. Clearly there is a push. I understand that its for climate benefits but it feels very coordinated. edit: didn't realize the attention I would get. Let me add someone answered my question -- a good product market fit and people talking is probably where the push came from. That said HV…

my friend is building his house and is putting in 4 heat pumps (big house). The problem is we just lost power for 4 days and 2 years ago we lost power for 5 days. He is discovering that electric heat uses massive amounts of electricity and there is no way to get a residential generator big enough to power them all. He might not even be able to power one (they can use in excess of 20kw).

I would never get electrical water heater, stove, and heater for that reason.

Re: How a heat pump works

#97

Post by wongarsu »

megaman821 wrote: post #91
oceanplexian wrote: post #85

Earlier quoted context omitted.

An overlooked benefit is that they actually improve comfort over a boiler in a dry climate, so if you live somewhere with low humidity they help keep the air less dry. They also give you heating and cooling.. for places that don’t have Air Conditioning it’s a worthwhile upgrade.

I assume in home that don't have ACs, that they also don't have ducts. Do these ductless homes filter their air, control home humidity, or bring in fresh air from outside?

"Ductless homes" usually circulate hot water through radiators. If you switch to a heat pump, nothing's stopping you from circulating cold water in the summer, though obviously there is a limit on the temperature delta (you can heat water much more than you can cool it). Bringing in fresh air is a manual process (open the windows), and filtering air or controling humidity is then left to seperate appliances, if done at all. Though small fans to the outside for forced ventilation are gaining some popularity for giving you automatic air exchange and filtration.

Re: How a heat pump works

#98

Post by bmicraft »

PragmaticPulp wrote: post #70
wongarsu wrote: post #27

Earlier quoted context omitted.

For a long time the main problem of heat pumps was that while they are more efficient, a kilowatthour of gas or oil is much cheaper than a kilowatthour of electricity. But in the last two years natural gas prizes have gone crazy, removing that price disadvantage. Of course heat pumps emitting no particulates and being able to run on renewables are also good reasons, especially as the health impact of living in cities…

Heat pump technology has also improved significantly. You can now buy heat pumps that remain efficient down to very low temperatures, which makes them appropriate for a larger range of climates now. Many models are in very high demand. Some of the units I looked at recently were back ordered so far that I was told to pick something else if I expected to have it within the year. The demand is very high because the tec…

Yeah it almost makes the opposite of sense. If manufacturers are already backordered a year in advance why would they still throw money at marketing

Re: How a heat pump works

#99

Post by kwhitefoot »

helen___keller wrote: post #30
boringg wrote: post #7

What is going on? Is there a global push to get everyone to switch to heat pumps. It seems that there is heat pump content everywhere. Clearly there is a push. I understand that its for climate benefits but it feels very coordinated. edit: didn't realize the attention I would get. Let me add someone answered my question -- a good product market fit and people talking is probably where the push came from. That said HV…

I’ve been independently interested in heat pumps because I need to replace my old end-of-life system and I’ve been interested if a modern cold-weather mini split system is a better investment. There’s lots of conflicting info I’ve found on if heat pumps perform in freezing weather and at what kind of efficiency. I’m sure there’s others in my position.

Heat pumps sold in Norway are claimed to work down to -30°C. See, for instance, the Samsung Nordic Extreme: https://www.elkjop.no/product/hjem-rengjoring-og-kjokkenutst...

I don't know what the coefficient of performance is at that temperature though.

Re: How a heat pump works

#100

Post by Silverback_VII »

boringg wrote: post #7

What is going on? Is there a global push to get everyone to switch to heat pumps. It seems that there is heat pump content everywhere. Clearly there is a push. I understand that its for climate benefits but it feels very coordinated. edit: didn't realize the attention I would get. Let me add someone answered my question -- a good product market fit and people talking is probably where the push came from. That said HV…

preparations for nuclear winter.
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