One reviewer credited Ecobee with making a furnace work properly after a previous thermostat failed with the system.
Pros: conventional HVAC compatibility, touchscreen responsiveness
Cons: presence-based automation
Best Smart Thermostats for conventional HVAC compatibility
A reviewer with a furnace and air conditioner framed conventional HVAC wiring as straightforward and low-friction.
Pros: Wi-Fi stability, Apple Home/HomeKit support
Cons: utility demand-response support, HVAC system compatibility depth
General 24V conventional compatibility came across as suitable for common household systems.
Pros: comfort consistency, privacy controls
Cons: heat pump compatibility, included C-wire adapter