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Furnace Servicing

Gas furnaces should be serviced periodically to ensure that they operate safely and efficiently. You can perform some of the most important maintenance tasks yourself.

The filter in your furnace or heat pump protects the blower, heating coils, and cooling coils from dirt. If these heating components get dirty, they are difficult and expensive to clean. Changing or cleaning your filters helps protect this critical equipment, and improves both heating and cooling efficiency.

Furnace filters should be changed or cleaned every few months – check yours periodically to see how quickly it gets dirty. The most common filters are made of a fiberglass mat mounted in a cardboard frame. These are disposable, and you can buy them from home improvement stores. Other filters are made of washable plastic fibers. You can clean these with soap and warm water either in the bathtub or outdoors with a hose.

Other furnace maintenance tasks should be performed by a professional. Have a heating contractor perform the following cleaning chores and safety checks every few years.

Measure the furnace's combustion efficiency, and make the required adjustments.
Confirm that the chimney removes combustion gases from the home under all conditions.
Clean the air-conditioning coil because a dirty coil impacts both heating and cooling.
Clean the blower. Oil the blower motor as needed.
Check for cracks or holes in the heat exchanger.

If you don’t change filters or your filter doesn’t fit properly, the blower will get dirty and need cleaning. If the blower is dirty, the air-conditioning coil is also probably dirty.

If you hire a heating contractor to perform periodic maintenance, it also gives you a chance to learn more about your heating system. Ask where the filter is located, and how it is changed. Also, find out where your system's main switch is, so you can turn it off in an emergency.

See Homeowners Guide to Building Performance 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 Mechanical Systems Field Guide.