The best way to ensure that your HVAC system will be compatible with the Sensi is to visit sensicomfort.com/tools and input your information into their Thermostat Compatibility Checker. Please note that a C-wire connection is necessary, which means that your thermostat must have a wire connected to the “C” terminal. If you don’t have a C-wire, please reach out to our support team at support@ecoventsystems.com to discuss your options.