Before heating season: check your HVAC filter

The first cool stretch of fall is a useful reminder to check the HVAC filter. A dirty filter can restrict airflow, but the right replacement depends on the equipment and filter rack in your home.

Find the filter without guessing

Many systems use a filter at a return grille, furnace cabinet, or air handler. Turn the system off before opening an access panel. If you do not know where the filter belongs, consult the equipment manual or ask your service company. Do not place a filter where the system was not designed to use one.

Read the existing filter first

Check the size printed on the frame and the airflow-direction arrow. Match both when you replace it. A high-efficiency filter is not automatically the best choice: a system that was not designed for a restrictive filter may lose airflow. If you want to change filter rating, ask an HVAC professional what is appropriate for your equipment.

Notice signs that need more than a filter

Uneven heat, unusual sounds, a burning odor, repeated cycling, water around the equipment, or a system that will not start are reasons to call a qualified technician. Do not remove panels beyond normal filter access or attempt electrical work.

For the bigger seasonal picture, use the HVAC maintenance checklist before scheduling a service visit.

Sources

• U.S. Department of Energy: Maintaining your air conditioner

Be ready for the conversation

3 questions to ask your qualified professional

1. 1What condition did you observe, and what evidence supports that conclusion?
2. 2What options fit this home, and what tradeoffs should I understand?
3. 3What exactly is included and excluded from the written scope?