My 2022 Vaillant model can operate down to -25C, and has a backup electrical heating element built in for when it gets colder than that. https://www.vaillant.c

My 2022 Vaillant model can operate down to -25C, and has a backup electrical heating element built in for when it gets colder than that. https://www.vaillant.com/home/products/air-to-water-heat-pump-system-arotherm-plus-12096.html https://www.vaillant.com/home/products/air-to-water-heat-pum...