It depends on the unit. Some (Mitsubishi FE12NA) have a COP of 1.75 even at -10F / -20C. See Table 6:
* https://www.nrel.gov/docs/fy11osti/52175.pdf
check chart on: https://www.researchgate.net/figure/Coefficient-of-performan...
It depends on the unit. Some (Mitsubishi FE12NA) have a COP of 1.75 even at -10F / -20C. See Table 6:
* https://www.nrel.gov/docs/fy11osti/52175.pdf