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I wonder how much of this heat pump argument was miscommunication. My personal experience is that heat pumps don't work worth a damn in below-freezing weather,

I wonder how much of this heat pump argument was miscommunication. My personal experience is that heat pumps don't work worth a damn in below-freezing weather, and always need to resort to resistance ("emergency") heating, which is extremely inefficient and expensive. Of course, my experience is with frequently decades-old units, or at best whatever cheap-o unit the landlord bought, not the very latest state-of-the-art system from the best manufacturer. The other thing I've found with heat pumps is that, even when they are "heating" the air, it feels cold. The problem is they're efficiently heating the air only by a few degrees and blowing it around, but when slightly warmer-than-ambient air blows in your face, it feels cold. Gas-fired furnaces don't do this: they heat the air much, much more than ambient temperature, so it actually feels quite warm when blown in your face. (The problem here is frequently poor placement of vents, but this is common with homes and also offices.)

xethos 3y ago
Sounds like you might be after a cold-climate [0] heat pump. They'll use advances in things like variable speed compressors and flash / vapor injection to draw useful heat from the air at well below -5C, without the need for auxillary heat sources like resistance heat. I'm doubtful it was simply mis-communication. Another point of contention was that heat pumps can be over 100% efficient - to the point that asking "Will they be more than 100% efficient with outside temps at 15C or 25C, and in indoor target of 20C?" got an emphatic no. That's less a miscommunication than a poor education, IMO. [0] https://en.wikipedia.org/wiki/Air_source_heat_pump#In_cold_climates https://en.wikipedia.org/wiki/Air_source_heat_pump#In_cold_c...
- shiroiushi 3y ago
  "Miscommunication" was probably poor wording on my part. What I meant was that their experiences, like mine, probably involved years or even decades of poor experiences with heat pumps in cold weather, so they were assuming that heat pumps haven't significantly improved in that regard.

xethos 3y ago

Sounds like you might be after a cold-climate [0] heat pump. They'll use advances in things like variable speed compressors and flash / vapor injection to draw useful heat from the air at well below -5C, without the need for auxillary heat sources like resistance heat. I'm doubtful it was simply mis-communication. Another point of contention was that heat pumps can be over 100% efficient - to the point that asking "Will they be more than 100% efficient with outside temps at 15C or 25C, and in indoor target of 20C?" got an emphatic no. That's less a miscommunication than a poor education, IMO. [0] https://en.wikipedia.org/wiki/Air_source_heat_pump#In_cold_climates https://en.wikipedia.org/wiki/Air_source_heat_pump#In_cold_c...

shiroiushi 3y ago
"Miscommunication" was probably poor wording on my part. What I meant was that their experiences, like mine, probably involved years or even decades of poor experiences with heat pumps in cold weather, so they were assuming that heat pumps haven't significantly improved in that regard.