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DIY Thermostat Upgrade

Electrical, Energy Efficiency, HVAC, Related Products May 20, 2008 Matt Weber

Install a programmable thermostat for increased temperature control and energy savings.





If you’ve not yet upgraded your thermostat to a programmable unit, then you’re behind the times like parachute pants. You’re probably throwing away money on unnecessarily high energy bills. And you aren’t doing Mother Earth any favors, either.

Programmable thermostats automatically adjust your home’s temperature settings several times a day to fit your lifestyle. These units contain no mercury and are more accurate than manual thermostats. According to the U.S. Department of Energy, when used properly programmable thermostats can save about $150 per year. This means the extra money spent on a programmable unit is usually recouped in a year. Plus, these thermostats are better for the environment, since using less energy helps reduce greenhouse gas emissions associated with energy production.

When selecting a thermostat, look for the Energy Star logo, which is the U.S. government’s cattle brand indicating the product meets strict energy-efficiency guidelines. These thermostats offer four pre-programmed energy temperature settings that anticipate when the system should scale back heating or cooling. In the winter, program the heat to kick on during your commute homeward, so you step into a warm, comfortable house. In the summer, keep air conditioning low in the morning so your system isn’t cooling an empty house while you’re at work. The versatile programming also benefits the many homeowners who work outside the home during the week but keep a different schedule on the weekend.


Features and Models

All of the Energy Star-qualified programmable thermostats include four default program periods per day, allowing you to save money while you’re away or sleeping. They maintain accuracy within 2 degrees to keep the temperature at an even level. Programmable thermostats typically feature digital, backlit displays; touch-pad screen programming; voice and/or phone programming; “hold/vacation” features; indicators that notify when it’s time to change air filters; and indicators that signal malfunctioning of the HVAC system. With so many options and features, it’s easy to create a heating/cooling schedule to fit individual needs.

The D.O.E’s Energy Star program qualifies the following three types of programmable units:

7-day models. These units are the best choice if your daily schedule has a tendency to change. By letting you set different programs for different days, these models offer the most flexibility—with four possible temperature periods per day.

5+2-day models. These units use the same schedule every weekday and another schedule for weekends.

5-1-1 models. This third type allows you to keep one schedule Monday through Friday, another schedule on Saturdays, and a third on Sundays.

Shown here is the old model before we replaced it.


Thermostat installation is a fairly simple chore. Typically, all that’s required is a slotted screwdriver, small Philips screwdriver, hammer, electric drill/driver, a 3/16-inch bit and two AA batteries. First step is to cut off the electricity to the thermostat and furnace. Remove the existing thermostat cover, thermostat and wall plate, which are usually fastened with screws and plastic push tabs.

Disconnect the wires and then unscrew the wall plate from the wall.

Take off the cover and unscrew the thermostat of the old unit.