Energy Saving Tips

Proper Operation and Maintenance

How you operate heating system controls and maintain the equipment can have a large effect on your heating bills. People living in identical houses can have utility bills that vary widely, with some families paying 50% more than others. Maintenance should be performed regularly, about once a year.                                       

Check the thermostat. In all heating systems, turn down thermostats when you don’t need the heat. In most homes, you can save about 2% of your heating bill for each degree that you lower the thermostat (if the turndown lasts a good fraction of the day or night). Turning down the thermostat from 70°F to 65°F, for example, saves about 10% ($100 saved per $1,000 of heating cost). Programmable thermostats, which automatically adjust the temperature setting one or more times per day, are widely available (see previous section).

Did You Know? Setting your thermostat back 10°F for eight hours at night can save about 7% ($70 saved per $1,000 of heating cost).

You might also be able to turn the thermostats down somewhat when you’re in the room if you do a little buttoning up of the house (see Building Envelope). Turning down thermostats even when you are in a room doesn’t mean being uncomfortable. In fact, you can actually be more comfortable at a lower temperature setting under the right conditions. Eliminating temperature stratification in a room where the floor is a lot colder than the ceiling will help the most, and getting rid of air infiltration and cold drafts is the best way to do it. Covering windows at night with blinds or drapes also helps, as does higher humidity. Buy some house plants or a humidifier, but don’t add so much moisture that you start seeing condensation on your windows.

Maintaining Forced-Air Systems. Furnaces and heat pumps require regular maintenance to help keep air distribution working.

  • Clean or replace air filters. Standard 1” deep fiberglass filters on warm-air furnaces and heat pumps should be checked once a month during the heating season and cleaned or replaced as necessary. Dust blocks the airflow and forces the blower to work harder, which raises electric bills and can lead to blower failure. These filters cost about $1 apiece and can usually be purchased at hardware stores. Some more expensive filters, generally much deeper and pleated, can run for 6-12 months before replacement.
  • Clean registers. Warm-air registers (particularly the return registers) should be kept clean and should not be blocked by furniture, carpets, or drapes.
  • Check duct dampers. Often, air ducts have dampers (adjustable metal flaps) in them to control flow. Shut off or turn down dampers and registers that heat the basement. Other dampers and registers can be turned down or off to control heat flow to various rooms. Unused rooms should be kept cooler than occupied rooms to save energy. Don’t close off too much airflow, though, because it may cause trouble for the fan.

Maintaining Hot Water and Steam Systems. When performing maintenance on hot water and steam heating systems, you may come in contact with dangerously hot water and steam. Use caution. If you’re uncertain about how to do something, call a service technician (or your landlord, if you rent).

  • Keep baseboards and radiators clean and unrestricted by furniture, carpets, or drapes. Air needs to freely circulate through them from underneath. Also, do not cover tops of radiators.
  • Bleed trapped air from hot water radiators. Trapped air keeps radiators from performing properly. Use a radiator key to bleed air out of hot water radiators once or twice a season. Hold a pan under the valve and open it until all the air has escaped and only water comes out. If you are not mechanically inclined, you may want to have the technician show you how to do it the first time.
  • Follow prescribed maintenance for steam heat systems, such as maintaining water level, removing sediment, and making sure air vents are working. Check with your heating system technician for specifics on these measures and use caution: steam boilers produce high-temperature steam under pressure.

Adjust the aquastat. This is the thermostat that regulates the temperature of the hot water boiler. Normally, the aquastat keeps water in the boiler around 160–180°F. In milder weather, however, you don’t need boiler water that hot. The aquastat of a condensing boiler can be set manually to 120–140°F, reducing fuel consumption by 5–10%. (If you have a non-condensing boiler or your boiler has a tankless coil for domestic hot water, you may not be able to turn the aquastat down this far.) The aquastat control is usually located in a metal box connected to the boiler. If you cannot locate it, ask your service technician for assistance. See the modifications section for information about modulating aquastats