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DIY Troubleshooting Guide
How to Change Your HVAC Air Filter
Properly swapping your air filter improves air quality, protects equipment, and lowers utility bills.
DifficultyEasy
Est. Time⏱️ 5 minutes
SuppliesCorrect sized HVAC filter
1
1Step
Locate Your Filter Slot
Find the filter slot behind the return air grille on a wall/ceiling, or directly slotted into the indoor furnace/air handler unit in a closet or attic.
Context / Why
This is where the indoor air is pulled into the system before being conditioned and pushed back out.
2
2Step
Note the Airflow Direction
Look for the printed arrow on the edge of the old filter showing airflow direction. It should always point TOWARD the HVAC unit, not away from it.
Context / Why
Filters are designed to catch debris on one specific side to maintain structural integrity under air pressure.
3
3Step
Slide in the New Filter
Carefully remove the old filter and slide in the new one, ensuring the airflow arrow matches the correct direction and the filter sits completely flush without gaps.
Context / Why
Any gaps will allow dirty air to bypass the filter and foul up your system's internal components.
Still experiencing issues?
If you completed the DIY steps and your system is still not functioning properly, it may require a professional diagnosis.
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