TEST: How often should I change my furnace filter?
A quick guide to furnace filter changes for New Hampshire homes.
Updated November 3, 2026
This is a TEST help article, published to check that help articles reach the website through the publish job. Most 1-inch filters should be changed every one to three months; thicker media filters last six to twelve months.
Signs it's time
- The filter looks grey or clogged
- Airflow from the vents feels weaker
- More dust around the house