| >>> Mine struggles if it gets below 30, and might as well not exist below 10. They're not great at low temps. >> > What percentage of the (US) population gets temperatures like that? That's generally mostly IECC Zone 7 (though cold snaps in Zone 6) can happen: > A lot? e.g. Chicago gets it every year [citation needed] Per historical weather data: https://ashrae-meteo.info/v2.0/index.php?lat=41.960&lng=-87.... It is warmer than -16C/3F at Chicago (O'Hare) for 99% of the time (i.e., except for 4 days a year), and warmer than -18.7C/-2F for 99.6% of the time (2 days). ASHRAE are the folks that publish the heating/cooling standards that are used in building codes for estimate heating/cooling equipment capacities (Manual J) and selecting the right equipment (Manual S). Here's a PDF with a lot of locations in the US and CA (and other countries further down), and if you look under the "Heating DB" column, you'll find very few US locations that have -30F under the 99% (or even 99.6%) sub-columns: * https://www.captiveaire.com/catalogcontent/fans/sup_mpu/doc/... So unless you're in AK, MN, or ND, long runs of temperatures colder than -20F/-30C don't happen too often. Of course if you have a leaky house with little insulation, you're throwing money out the window/door, so the first consideration for a good ROI is better air sealing and insulation. |
Also..
> It is warmer than -16C/3F at Chicago (O'Hare) for 99% of the time (i.e., except for 4 days a year), and warmer than -18.7C/-2F for 99.6% of the time (2 days).
If my heat doesn't work for those days, I'm kind of boned. Four days per year without a working heat pump? That's a mess.