Owner's Manual
Page 19
... 69-1921EFS-01 Install fresh batteries immediately when the REPLACE BATTERY warning begins flashing. If batteries are optional (to provide backup power) if your thermostat was wired to remove Replace Battery Insert fresh AA alkaline batteries, then reinstall battery holder. All other settings are depleted. The warning flashes about two months before...
... 69-1921EFS-01 Install fresh batteries immediately when the REPLACE BATTERY warning begins flashing. If batteries are optional (to provide backup power) if your thermostat was wired to remove Replace Battery Insert fresh AA alkaline batteries, then reinstall battery holder. All other settings are depleted. The warning flashes about two months before...