How do I replace the battery in a Honeywell thermostat?

To replace the battery in a Honeywell thermostat, first, remove the thermostat from the wall by gently pulling it off. Locate the battery compartment on the back of the thermostat and open it. Take out the old batteries and replace them with new ones, making sure to match the positive and negative ends correctly. Close the battery compartment and reattach the thermostat to the wall.