What power requirements does the Th6320Wf2003 thermostat need?
The thermostat requires 24 VAC power with a common ('C') wire connection. It does not work with electric baseboard heat (120-240V) or millivolt systems, and is compatible with most heating, cooling, and heat pump systems.
From the official Honeywell Lyric T6 Pro Wi-Fi Smart Thermostat manual, page 1
Have a follow-up question?
Answers from the official manual.
Common questions