If there are only 4 wires to your existing thermostat (i.e. there is no C wire), you can use the ecobee Power Extender Kit to power your thermostat. Diode W Y Removeable Cover Wiring Channel Step 1. Install Wiring Harness Step 2. Install Diode The Power Extender wiring harness must be installed in an indoor, dry location, near the HVAC equipment.. Not sure if you need a PEK. Use the ecobee Thermostat Compatibility Checker to find out.ecobee Smart Thermostats are designed to work without a C wire in most homes. But some systems may require a C wire for consistent power, with the power extender Kit a cost-effective and efficient solution for homes without a common wire
The Power Extender Kit comes with all ecobee thermostats except Smart Thermostat Essential and Smart Thermostat Lite (but is compatible with those models, as well) and only works with 24 VAC systems.. Skip the expensive common wire installation with our do-it-yourself ecobee Power Extender Kit. It's smart, straightforward, and a great way.. Using the Power Extender Kit. If your thermostat doesn't have a C wire and there are no extra wires to use, you can use the Power Extender Kit (PEK) to complete the installation. Article: Installing with the PEK. Using a C Wire. If you have an extra wire available and your air handler control board has a C terminal. Article: Installing with a C.