The Honeywell RTH230B is a programmable residential heating and cooling thermostat. The device can be programmed for both weekdays and weekends and has a filter change reminder and an early-start function. If used as directed, the thermostat can increase the overall energy savings in a home up to 30 percent or more, according to the manufacturer. The thermostat comes with a limited warranty. If problems occur with the unit, some troubleshooting efforts may prove to be useful prior to contacting Honeywell for assistance.

Step 1

Replace the batteries if the thermostat is not functioning or the "Battery Low" light is illuminated. Pull the battery cover forward from the front of the unit and replace the batteries. Push the battery cover closed.

Step 2

Check the household fuse or circuit breaker if there is no power to the thermsotat. Replace or reset as needed.

Step 3

Place the "Selector Switch" to "Heat" if the unit is not heating as expected. Use the arrow keys to adjust the thermostat to the desired temperature and set the fan switch to "Auto."

Step 4

Set the "Selector Switch" to "Cool" if the unit is not cooling as expected. Use the arrow keys to adjust the thermostat to the desired temperature and set the fan switch to "Auto."