Owner's Manual
Page 12
..., and do not require battery power. 10 AA alkaline batteries. 69-1923EFS-01 MCR29411 Batteries are optional (to provide backup power) if your thermostat was wired to run on AC power when installed. Install fresh batteries immediately when the REPLACE BATTERY warning begins flashing.
..., and do not require battery power. 10 AA alkaline batteries. 69-1923EFS-01 MCR29411 Batteries are optional (to provide backup power) if your thermostat was wired to run on AC power when installed. Install fresh batteries immediately when the REPLACE BATTERY warning begins flashing.