While traditional thermostats only require power through the four classic wires, smart thermostats typically require low- voltage power all day. This comes from an additional fifth wire called the ...
Once wired and installed, smart thermostats connect to other devices in your home through Wi-Fi or occasionally via Z-Wave. Once connected, they're compatible with major smart home devices.
Be sure to check out the useful Nest Thermostat Compatibility Tool at Google if you have questions about your exact system. As for the actual installation, you’ll be guided through the process ...