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A comment on Heat pumps of the 1800s are becoming the technology of the future. Parent comment

Re:Heat pumps of the 1800s are becoming the technology of th... by rootusrootus on Monday January 16, 2023 @04:15PM (#34405576)
Indeed, sounds like a problem with the fan. My 3000sf house uses 1100W for the fan, and about 4000W for the heat pump. I expect converting to mini-splits would increase, not decrease my overall power usage.
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Re:Heat pumps of the 1800s are becoming the technology of th... by fifteenforty on Monday January 16, 2023 @04:23PM (#34405669)
700W for the gas ducted heater fan. That’s the steady state energy consumption of all 3 units heat pumps running simultaneously. This is a small house of 100 square metres/1100 square feet.
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Re:Heat pumps of the 1800s are becoming the technology of th... by fifteenforty on Monday January 16, 2023 @04:25PM (#34405693)
Obviously a new EC fan will be more efficient than a 20 year old AC fan, but I’m talking about a retrofit application here.
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Re:Heat pumps of the 1800s are becoming the technology of th... by _benedict on Monday January 16, 2023 @04:18PM (#34405608)
Pretty sure mini splits are significantly more efficient today, with SCOP of above 5, so that seems unlikely?
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Re:Heat pumps of the 1800s are becoming the technology of th... by rootusrootus on Monday January 16, 2023 @04:35PM (#34405796)
I recently replaced my [central, ducted] heat pump, and the new one is rated with a 4.981 SCOP. It's fairly efficient, but not the most efficient on the market.
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Re:Heat pumps of the 1800s are becoming the technology of th... by fifteenforty on Monday January 16, 2023 @04:39PM (#34405830)
-40% for the duct heat loss
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Re:Heat pumps of the 1800s are becoming the technology of th... by rootusrootus on Monday January 16, 2023 @06:03PM (#34406705)
That seems kind of high for insulated ducts, where does that number com from?
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Re:Heat pumps of the 1800s are becoming the technology of th... by fifteenforty on Monday January 16, 2023 @06:18PM (#34406881)
US energy.gov
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Re:Heat pumps of the 1800s are becoming the technology of th... by dahfizz on Monday January 16, 2023 @07:39PM (#34407630)
It would be nice to actually link the source[1] (PDF).

The stat is that you lose between 25-40% efficiency for "typical" existing installations. The document goes on to explain that an insulated duct which doesn't leak doesn't have this kind of efficiency loss.

[1] https://www.google.com/url?q=https://www1.eere.energy.gov/bu...

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Re:Heat pumps of the 1800s are becoming the technology of th... by fifteenforty on Monday January 16, 2023 @04:34PM (#34405789)
This unit runs at about 5
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