Resetting your thermostat while you’re asleep or away can help save money on heating and cooling costs. Installing an automatic setback thermostat or programmable thermostat will allow you to do this without having to sacrifice comfort.
A programmable thermostat allows you to adjust the time when you want your heating and air conditioning turned on or off according to your schedule. Programmable thermostats are able to store and repeat multiple daily settings (6 or more temperature settings per day). These settings can be manually overridden without affecting the rest.
One common misconception about thermostats is that they work harder than normal to heat your space to comfortable temperatures after being set back. This can lead to little savings. In reality, if your house temperature is lower than what is is normally set at, it will lose more energy because of the temperature of it’s environment. Our general rule is, heat loss is slower if the temperature inside is lower than the outside.
The lower your house temperature stays at, the more energy your house uses. It will have used less energy to heat it than it would at a higher temperature. This principle applies to setting your thermostat higher in summer. A higher interior temperature will slow down heat flow and save energy on your air conditioner. To learn more about heating systems and thermostats, check out our infographic on home heating.
Limitations for Homes with Heat Pumps, Electric Resistance Heating, Steam Heat, and Radiant Floor Heat
Heat pumps are not recommended to use with a programmable thermostat. A heat pump works in a cooling mode like an air conditioner. Turning up the thermostat manually or using a programmable thermostat will help you save money and energy. However, heat pumps in it’s heating mode can be inefficient when the thermostat is set back. This could cause them to work inefficiently and cancel any savings made by lower temperature settings. The most cost-effective option is to keep the temperature at a moderate level. However, companies have recently started selling programmable thermostats that are specifically designed for heat pumps. This makes it more cost-effective to set the thermostat back. These thermostats often use specific algorithms to reduce the need for backup electric resistance heat systems.
The thermostats required for electric resistance systems such as electric baseboard heating require the ability to control 120-volt and 240-volt circuits. Few companies make line-voltage programmable thermometers.
Some people believe that radiant floor heating and steam heating systems have a slow response time, sometimes lasting several hours. Some manufacturers offer thermostats that monitor the heating system’s performance to determine when it should be turned on to maintain comfortable temperatures at set times.
Alternately, you can set a thermostat to cool off well before you go to bed or leave. It will then return to the normal temperature about two to three hours after you return home. Although this may seem complicated at first, it can be done with some trial and error.
Choosing and Programming a Programmable Thermostat
The majority of programmable thermostats can be either digital or electromechanical or a mix of the two. While digital thermostats have the most features, including multiple setback settings, overrides and adjustments for daylight saving time, they can be more difficult to program. Many electromechanical systems use sliding bars or pegs and are easy to program.
Consider when you usually go to bed and when you wake up each morning before programming your thermostat. You might prefer to sleep in cooler temperatures during winter so you should program your temperature set back to be set a little earlier than the time you go to bed. You should also consider the time and schedules of all members of the household. It would make the most sense to adjust the temperature during unoccupied periods of the day, that fit most people in your household’s schedule.
Your thermostat’s location can have an impact on its efficiency and performance. To avoid “ghost readings” and unnecessary furnace or air conditioner cycling, read the manufacturer’s instructions. A thermostat should be installed on an interior wall, away from sunlight, drafts, doors, windows and skylights. It should be placed where natural room air currents (warm air rising, cool water sinking) occur. Natural air movement will be blocked by furniture, so don’t place furniture in front or below your thermostat. Make sure that your thermostat is easily accessible for programming.