Honeywell T8700B Owner's Manual - Page 9

Symptom Heating does not come on. Temperature setting is too warm or too cool. Blank display. Displays only time and not temperature. Time flashing. Corrective Action Check that the heat setpoint is above room temperature. Check that the system switch on the thermostat is set to HEAT. Check the system fuse or circuit breaker and replace or reset if necessary. Check power to the heating equipment. Adjust the temperature by pressing either the or key. Check that switch to furnace is on. Check that the thermostat is properly latched on wallplate. Power is interrupted to the thermostat. Power is interrupted. The current time is maintained up to 20 minutes after power interruption. Reset heating setpoint. Power was interrupted longer than 20 minutes. Reset clock. 9 69-1181