A fully electric heating system that combines a cold climate heat pump with an electric heater as a backup heat source is a common setup for homes in cold climates.

During normal operation, the heat pump will extract heat from the outside air and transfer it into the home to provide heating. However, in extremely cold temperatures, the heat pump may struggle to extract enough heat from the air, and the electric heater will turn on to provide additional heating.

The benefit of this type of system is that the heat pump is highly efficient at extracting heat from the air, which means it requires less electricity to provide heating compared to a traditional electric heater. This can result in lower energy bills and reduced environmental impact.

Additionally, because the electric heater only operates as a backup, it can extend the lifespan of the heat pump by reducing the number of times it needs to operate in extreme conditions.

Overall, this fully electric heating system combination can be an effective and efficient solution for homes in cold climates, providing both comfort and cost savings.