How Often Should You Change an AC Filter (and How to Do It Right)
Changing your AC filter is one of the quickest ways to improve air quality, reduce energy costs, and extend the life of your system. The best part? You can do it yourself in just a few minutes. Here’s how often to replace it—and exactly how to get it done the right way.
How Often Should You Change It?
- Every 1–2 months if you have pets, allergies, or high dust.
- Every 2–3 months for typical households.
- Monthly during peak cooling/heating seasons.
- Vacation or rarely used homes: every 3–4 months (still check monthly).
Pro tip: Hold the old filter up to a light. If you can’t see light through it, it’s time to replace.
What You’ll Need
- Replacement filter (match the size printed on your current one, e.g., 16×25×1)
- Optional: gloves, a small trash bag, and a flashlight
Step-by-Step: How to Change an AC Filter
- Turn the system off at the thermostat to keep unfiltered air from circulating.
- Locate the filter. It’s either:
- Behind a return air grille (often in a hallway or ceiling), or
- Inside the air handler/furnace (closet, attic, basement, or garage).
- Check the size printed on the filter frame (e.g., 20×20×1). Buy the same size.
- Remove the old filter carefully to avoid knocking dust into the duct.
- Install the new filter with the airflow arrow pointing toward the unit (same direction air travels).
- Close the panel/grille and turn the system back on.
Choosing the Right Filter
- Fiberglass: Budget option, least filtration, change more often.
- Pleated (MERV 8–11): Great balance of airflow and filtration for most homes.
- High-MERV (12+): Better capture of fine particles; ensure your system can handle the airflow.
Why It Matters
- Improves indoor air quality (dust, dander, pollen)
- Helps your system run efficiently—lower energy bills
- Prevents breakdowns from restricted airflow
Need More Than a Filter Change?
If your system is still struggling—odd noises, hot/cold spots, or weak airflow—book a pro in seconds. OneTap connects you to trusted local technicians fast.
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