Some thermostat may have a feature called Emergency Heat where when set, it will shut off the heat pump. It will then turn on the strip heat which becomes the primary source of heating. This feature should only be used for a while as the energy cost is usually higher than a heat pump system. The terminal used is E.
The EM HT (Emergency Heat) feature allows the user to use a backup heat ... This is typically used until a heating and/or cooling contractor can ... Articles · Thermostat Wiring Compatibility Checklist · Product Registration ...
Thermostat Wiring Colors Code - Always follow the thermostat manufacturers ... E – This terminal is for heat pumps and stands for Emergency Heating.