The US Department of Energy reports that decreasing the temperature by 10 to 15’F for 8 hours (while you are at work or sleeping) can reduce heating bills by 5 to 10 percent. Programmable (or set-back) thermostats allow you to program different temperatures for mornings, daytime, evenings and nights on a different schedule for weekdays and weekends. Because you don’t need to change the temperature setting yourself, these thermostats (which start at about $40) can save up to $100 annually.
Some people are concerned that it takes extra energy to heat the house back up after the temperature has been reduced. But studies have shown that the energy required to heat the house back up equals the energy saved as it cooled down. You still save the energy that’s conserved while temperature is stable at the lower level.
Some tips on placing the thermostat is that the thermostat should be placed in an area that’s not prone to big temperature swings (such as beside an exterior door), but if you are replacing your existing thermostat, you may be limited to putting it where the old one was.
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