At very low outdoor temperatures, the heat pump may not be sufficient on its own for the building's full thermal load.
Bivalent point
It is the outdoor temperature at which the available power of the heat pump becomes equal to the thermal load of the building.
Below this point
A supplementary heat source may be required, such as an electric heating element or a secondary heating system.
Automation control
Activation should only occur when necessary, because the electric heating element has a lower energy efficiency than the heat pump.
Correct setting
The activation point depends on the building, the power curve of the pump, and the cost of energy.
