Heat pumps are central to enabling a zero-emission future. Cold climate heat pump water heaters enable electrification in more climate zones. Heating domestic hot water with a heat pump in cold ambient conditions is quite different from heating air for space heating. People often point to HVAC heat pumps, which can heat their home when the ambient temperature is 0°F or below, and ask why our heat pumps can’t make hot water when it is that cold. If they can do it, why can’t Nyle?