How cold can a ducted or ductless minisplit handle?
AlanB4
| Posted in Energy Efficiency and Durability on
I am curious at what temperature they can work down to and what kind of efficiency one would see at those temperatures?
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Alan,
This threat might be worth reading: https://www.greenbuildingadvisor.com/question/cold-weather-performance-reports-from-minisplit-owners
Very interesting, thanks.
Also in this thread Dana says
"There are a few mini-splits fully specified down to -22F/-30C, and many specified down to -13F/-25C, even more specified at -20C."
https://www.greenbuildingadvisor.com/question/best-heat-source-for-this-house#comment-164306
>"...and what kind of efficiency one would see at those temperatures?"
The COP of a cold climate mini-split runing balls to the walls fully maxed out speed at 0F will be in the 1.5-2 range, maybe a hair higher than 2 at 0F if it's modulating rather than maxed out. At full speed at whatever it's lowest specified temperature is, figure COP 1.5-ish. Below that temp it'll still be delivering heat, but at a somewhat lower COP too.
R410A refrigerant heat pumps don't have any capacity to speak of (at any efficiency) at temps below about -35F/-37C, due to the nature of the refrigerant at the operating pressures used, which makes them a poor fit as the sole heating source for an Arctic Ocean beachfront cabin. Even at atmospheric pressure it condenses at -46F/-51C.