Change an HVAC filter
10 minutes · Easy · Estimated materials $8–$30
Restore airflow and protect your equipment with the correct filter direction and size.
Likely cause
Filters load with dust over time, reducing airflow and making heating or cooling equipment work harder.
First safe check
Read the size printed on the filter edge before removing it.
Tools and materials
Tools
- Flashlight
- Phone camera
Materials
- Correct-size replacement filter
Step by step
- 1Turn the system off at the thermostat.
- 2Photograph the airflow arrow and filter orientation.
- 3Slide the old filter out without shaking it.
- 4Insert the new filter with its arrow pointing toward the blower.
- 5Close the cover, restore operation and record the date in My Home.
Common mistakes
- Installing the arrow backward
- Using a filter that is too restrictive
- Forgetting a second return
When to call a professional
Gas appliances
Most of this is yours to do. Call someone licensed if any one of these is true — it's a judgement call, not a defeat.
- You can smell gas anywhere in the room.
- A pilot light won't stay lit after two calm attempts.
- The job means loosening, moving, or capping a gas line.
- A carbon-monoxide alarm has sounded in the last month.
Heating and cooling
Most of this is yours to do. Call someone licensed if any one of these is true — it's a judgement call, not a defeat.
- The fix would involve refrigerant of any kind.
- The unit trips its own breaker or short-cycles.
- You see ice on the lines in normal weather.
- Airflow is fine but the system still won't hold temperature.
General guidance only. Codes and conditions vary. When in doubt, stop and use a licensed professional.