Google Nest thermostats are designed to work without a C wire in most homes, but for some systems, including heating-only, cooling-only, zone-controlled, and heat pump systems, you’ll need a Nest Power Connector or C wire. The Nest Power Connector is a simple, affordable alternative to a C wire if your heating and cooling system requires one to power your Nest Thermostat.

• Costs less than hiring an electrician to install a new C wire through your walls
• Installation is simple
  • It attaches to your furnace, air handler, or zone controller
  • It comes with simple instructions; no wiring or drilling required
• The Nest Power Connector is only compatible with 24 VAC systems; it won’t work with millivolt or high voltage systems
• The Nest Power Connector is the Nest thermostat C wire adaptor that’s designed specifically for Nest thermostats