Air filter at the return
The filter behind the return grille loads faster in a new house than the box it came in suggests. Drywall dust and sawdust from the build stay in the ductwork and in the house for months after closing, and they end up here.
- How often
- Every 3 months, more often with pets in the house
- How
- Check it sooner when pollen is heavy, and sooner again in a house that has just been finished. Note the airflow arrow on the frame, which points toward the air handler. Slide the old filter out, match the size printed on its edge, and slide the new one in facing the same direction.
- Call a licensed professional when
- Airflow is weak with a clean filter in place, or there is ice on the refrigerant lines at the outdoor unit.
- Worth knowing
- A restricted filter can freeze the coil. A no-cool call traced back to a filter that was never changed is not usually treated as a warranty item, so keep the receipts.