ecobee3 Wiring Diagrams – ecobee Support This diagram illustrates the wiring connections for a heat-pump system with auxiliary heating. W2, AUX and or E (Emergency) wiring connections will normally connect to the ecobee3 W1 terminal. ecobee3 manages auxiliary heating through the W1 & W2 (if there is more than 1 Thermostat Installation & Wiring Diagrams – ecobee Support I’m upgrading from ecobee3 to ecobee4, what wiring changes do I need to make? I currently own an ecobee3 and use a Power Extender Kit (PEK). Can I use the same PEK for the ecobee3 lite or ecobee4? I currently own a Smart Si and use a Power Extender Kit (PEK). Can I use the same Power Extender Kit for ecobee3 lite? Installation guide PDF fileStep 6. Power on ecobee3 Power your HVAC equipment back on. Your ecobee3 will automatically power on. If your ecobee3 does not power on, see page 27 for troubleshooting. Follow the on-screen instructions. ecobee3 will guide you through the setup, which includes: • Equipment configuration (HVAC and accessories) Ecobee3 Wiring Diagrams – Ecobee Support - Wirings Diagram Ecobee3 Wiring Diagram – ecobee wiring diagram air conditioner, ecobee wiring diagram heat pump, ecobee wiring diagram humidifier, Every electrical arrangement is made up of various diverse pieces. Each part should be set and linked to other parts in particular way. If not, the arrangement will not function as it ought to be.