Programmable thermostats can save a lot of heating energy if they are programmed correctly. The programmable thermostat toggles the room temperature back and forth between an energy-saving setting and a comfort setting. Check your programmable thermostat at least once a year to see that its settings match your lifestyle and preferences. Although all programmable thermostats are a little different, most have similar functions and they usually have a summary of programming instructions on the door that opens to reveal the programming buttons.
Arrow buttons. Usually there are two arrow buttons, up and down, that are used to adjust temperature. If you change the temperature setting and nothing else, it will usually change the temperature temporarily until the end of the current programming period. After that the thermostat will resume its programmed functions.
Clock settings. Check the time displayed on the thermostat – if you need to change it, there is usually a button for “Set Time”. Or there may simply be “hour” and “minute” buttons that you press until the right time appears on the screen. Pay attention to whether the time is AM or PM. Be sure to also set the correct day of the week. Usually there is a “day” button too.
Program settings. Most programmable thermostats can change the temperature setting four times a day. Often there are also two types of program days: weekdays and weekend days. To look at the program choose Program and toggle through the time and temperature settings for weekdays and weekends to see how they are now set. The time settings should match sleep, waking, leaving home, and returning home. The comfort temperature setting should start at waking or returning home. The economy setting should show a setting 5° to 15° lower for winter nights or for daytime periods when no one is home. While you’re looking at the setting for any day or time, you can change the time or temperature, using the arrow buttons.
Setting programmable thermostats is fairly intuitive. You find out how to view the program settings and change them to your liking. You can run the program, interrupt it temporarily, and allow the program to resume.
Hold temperature. If for some reason, you want the temperature to remain the same until you change it again, use the “Hold Temperature” button. This is useful, for example, if you are usually home on weekends but plan to be gone for the day and don’t want to heat your home. Later when you want to go back to the program, push the “Run Program” button.
See The Homeowners Handbook to Energy Efficiency or Residential Energy: Cost Savings and Comfort for Existing Buildings Chapter 6 for more information. For professional information about heating systems and energy efficiency see Saturn Hydronic Systems Field Guide.