Honeywell TH6110D1005 Owner's Manual - Page 19

ABbatotuetryyoruerplnaecwemtheenrtmostat FocusPRO® TH6000 Series ENGLISH Press and pull to remove Replace Battery Insert fresh AA alkaline batteries, then reinstall battery holder. MCR29467 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. The warning flashes about two months before the batteries are depleted. Even if the warning does not appear, you should replace batteries once a year, or before leaving home for more than a month. If batteries are inserted within two minutes, the time and day will not have to be reset. All other settings are permanently stored in memory, and do not require battery power. 17 69-1921EFS-01