Programmable ENERGY STAR thermostats serve homeowners on the go. Just program the thermostat to fit your schedule. The thermostat keeps rooms comfortable when you are home and adjusts to energy-saving levels when you are away. Increase the efficiency of your ENERGY STAR thermostat by setting it at energy-saving temperatures for long periods of time. This may be when you are at work or asleep at night. Do not override the pre-programmed settings. This reduces your energy savings. Make sure you have your new thermostat installed on an interior wall that is away from drafts, heat sources and direct sunlight.