what temperature should our energy furnace be set on in cold weather
1 7:45 a.m. : The family leaves the house and the thermostat is set to 56Â°F. 2  By turning their thermostat back 10Â° to 15Â° for 8 hours, the family can save 5% to 15% a year on their heating bill -- a savings of as much as 1% for each degree if the setback period is eight hours long.