( Note: As long as your current HVAC system wiring offers all the connections you'll need to install a smart thermostat — for the vast majority of smart thermostats, we're talking about C-wires (or "common" wires) — this is a relatively straightforward DIY project.
( Note: As long as your current HVAC system wiring offers all the connections you'll need to install a smart thermostat — for the vast majority of smart thermostats, we're talking about C-wires (or "common" wires) — this is a relatively straightforward DIY project. However, if your system needs to be retrofitted in any way, it's best to call the pros.)