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How well do they function? Do they provide nice consistent heat? How's the noise? Sorry to clog up HN with a random request of a product quality review but I'm

How well do they function? Do they provide nice consistent heat? How's the noise? Sorry to clog up HN with a random request of a product quality review but I'm in the market right now to replace my furnace as well. Thanks.

demondemidi 3y ago
Heat pumps need to come with an electric heater because pumps stop working below 30 deg F.
- headsupernova 3y ago
  This isn't true, the latest models work at temps far below that. There are still thresholds where you'd want another source, but they're very functional even in the upper Midwest.
- wtallis 3y ago
  They come with an electric heater, but they don't stop working until far below freezing point. It's normal for a heat pump to still be better than pure resistive electric heating even at 10°F.
- SOLAR_FIELDS 3y ago
  Ground source heat pumps are available that go down significantly lower than 30F. They are more expensive. Though running the electric wires is also very expensive due to their inefficiency. Typical heat pumps are often better suited for warmer climates because of this It also appears that the tech for the more typical air source heat pumps has improved significantly in recent years which makes it more viable for colder climates
  - virtue3 3y ago
    I believe they run a heat conductive fluid through heat exchange coils in the ground. This allows you to pump heat into the ground during winter and extract said heat (not sure how accurate this is) during the winter.
    - BobaFloutist 3y ago
      You're not storing the heat that's underground, it's just that the ground is a huge thing with massive heat storage capacity that doesn't notice weather as much as above ground does. If above ground ranges from 0-100 degrees F, underground likely ranges from like 64-68 degrees F, which makes it really energetically "cheap" to get to your preferred temperature range, heating to idk 70 at most and cooling to probably not even 65.
- Fuut 3y ago
  This is just not true at all. Why do you even respond if you don't know enough about heat pumps?
  - bluGill 3y ago
    It is practically true. Sure my heat pump can make heat below 28F - but it was sized for cool my house in summer and so it cannot make enough heat anymore and so I need the backup heat.
  - demondemidi 3y ago
    Oh, sorry, I guess I was brainwashed by the "anti heat pump mafia". I had this conversation with three HVAC installers but according to this thread any HVAC installer that speaks ill of heatpumps is old and stupid. Recently, I stayed at an AirBNB recently that had a heatpump and the temps dropped during the deep freeze and it was running 100% of the time and failing. The AirBNB owner said it was brand new and I would be responsible for excessive electricity use. They didn't charge me. Based on this, I am sooo glad I replaced my dead furnace with gas three years ago and steered clear of heat pumps. But do go on about how I don't know enough.
    - lkbm 3y ago
      Old heat pumps didn't do well in old temperatures. In the 80s and 90s, a heat pump couldn't handle freezing temps. Modern heat pumps do fine well below 0 degrees Celsius. Here's one that's great to -15 C and okay down to -25 C[0]. If you search cold-climate heat pumps, you'll find plenty of information about how modern heat pumps are fine in most the temperatures you'll find in most of the US (including up north). (I have heard that a lot of them are still only available in Europe, but you can definitely find some in the US.) [0] https://carbonswitch.com/best-cold-climate-heat-pump/ https://carbonswitch.com/best-cold-climate-heat-pump/
    - antisthenes 3y ago
      I mean, instead of an argument you responded with some kind of rant about your Airbnb experience. So his point still stands.
- huytersd 3y ago
  Not true, mine goes down to 23F with negligible decrease in efficiency and still functions after that, but with reduced efficiency.
gertlex 3y ago
One anecdote I've seen is that the right way to run them is to maintain a near-steady-state temperature in the house, including overnight. I'm not sure if that's maybe a bit extreme and just how they suggest use to non-savvy home-owners, but it makes sense... They're not going to blast out heat to raise the house temperature 10 degrees in an hour in the morning. Spreading heat-increase over several hours is more feasible. Good insulation presumably helps a bunch, too. For a similar reason, heat pump water heaters tend to have a larger storage tank, as they take longer to heat the water and you want more of a usage buffer.
- crazygringo 3y ago
  You don't need to run it overnight. But I do set a timer for mine to turn back on an hour before I get up. Because exactly -- it's not blasting hot air, it's merely circulating warm air. An hour beforehand works fine for mine though.
  - huytersd 3y ago
    Do you’ll not run your heat at night when it’s the coldest?
    - crazygringo 3y ago
      Just in the bedroom. Don't need it anywhere else.

demondemidi 3y ago

Heat pumps need to come with an electric heater because pumps stop working below 30 deg F.

headsupernova 3y ago
This isn't true, the latest models work at temps far below that. There are still thresholds where you'd want another source, but they're very functional even in the upper Midwest.
wtallis 3y ago
They come with an electric heater, but they don't stop working until far below freezing point. It's normal for a heat pump to still be better than pure resistive electric heating even at 10°F.
SOLAR_FIELDS 3y ago
Ground source heat pumps are available that go down significantly lower than 30F. They are more expensive. Though running the electric wires is also very expensive due to their inefficiency. Typical heat pumps are often better suited for warmer climates because of this It also appears that the tech for the more typical air source heat pumps has improved significantly in recent years which makes it more viable for colder climates
- virtue3 3y ago
  I believe they run a heat conductive fluid through heat exchange coils in the ground. This allows you to pump heat into the ground during winter and extract said heat (not sure how accurate this is) during the winter.
  - BobaFloutist 3y ago
    You're not storing the heat that's underground, it's just that the ground is a huge thing with massive heat storage capacity that doesn't notice weather as much as above ground does. If above ground ranges from 0-100 degrees F, underground likely ranges from like 64-68 degrees F, which makes it really energetically "cheap" to get to your preferred temperature range, heating to idk 70 at most and cooling to probably not even 65.
Fuut 3y ago
This is just not true at all. Why do you even respond if you don't know enough about heat pumps?
- bluGill 3y ago
  It is practically true. Sure my heat pump can make heat below 28F - but it was sized for cool my house in summer and so it cannot make enough heat anymore and so I need the backup heat.
- demondemidi 3y ago
  Oh, sorry, I guess I was brainwashed by the "anti heat pump mafia". I had this conversation with three HVAC installers but according to this thread any HVAC installer that speaks ill of heatpumps is old and stupid. Recently, I stayed at an AirBNB recently that had a heatpump and the temps dropped during the deep freeze and it was running 100% of the time and failing. The AirBNB owner said it was brand new and I would be responsible for excessive electricity use. They didn't charge me. Based on this, I am sooo glad I replaced my dead furnace with gas three years ago and steered clear of heat pumps. But do go on about how I don't know enough.
  - lkbm 3y ago
    Old heat pumps didn't do well in old temperatures. In the 80s and 90s, a heat pump couldn't handle freezing temps. Modern heat pumps do fine well below 0 degrees Celsius. Here's one that's great to -15 C and okay down to -25 C[0]. If you search cold-climate heat pumps, you'll find plenty of information about how modern heat pumps are fine in most the temperatures you'll find in most of the US (including up north). (I have heard that a lot of them are still only available in Europe, but you can definitely find some in the US.) [0] https://carbonswitch.com/best-cold-climate-heat-pump/ https://carbonswitch.com/best-cold-climate-heat-pump/
  - antisthenes 3y ago
    I mean, instead of an argument you responded with some kind of rant about your Airbnb experience. So his point still stands.
huytersd 3y ago
Not true, mine goes down to 23F with negligible decrease in efficiency and still functions after that, but with reduced efficiency.

gertlex 3y ago

One anecdote I've seen is that the right way to run them is to maintain a near-steady-state temperature in the house, including overnight. I'm not sure if that's maybe a bit extreme and just how they suggest use to non-savvy home-owners, but it makes sense... They're not going to blast out heat to raise the house temperature 10 degrees in an hour in the morning. Spreading heat-increase over several hours is more feasible. Good insulation presumably helps a bunch, too. For a similar reason, heat pump water heaters tend to have a larger storage tank, as they take longer to heat the water and you want more of a usage buffer.

crazygringo 3y ago
You don't need to run it overnight. But I do set a timer for mine to turn back on an hour before I get up. Because exactly -- it's not blasting hot air, it's merely circulating warm air. An hour beforehand works fine for mine though.
- huytersd 3y ago
  Do you’ll not run your heat at night when it’s the coldest?
  - crazygringo 3y ago
    Just in the bedroom. Don't need it anywhere else.