Furnace air filter — vacuum the return grille at each swap
Furnace filter
Furnace air filter tip: vacuum dust off the return air grille when you change the filter, so the new filter breathes and stays clean longer.
A new furnace air filter works best when air can reach it. Dust on the return grille slows airflow before the filter even sees it.
Give the return grille a pass with each furnace air filter
- Turn the system off at the thermostat before you start.
- Run a vacuum brush attachment across the return grille slats, top to bottom.
- Wipe any sticky spots with a damp cloth and let it dry.
- Slide in the new furnace air filter with the arrow pointing toward the furnace, then turn the system back on.
That is the beat: clean grille, fresh filter, same swap day. Nothing else to add.
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