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Air filters: the cheapest way to protect your AC
A clogged filter is behind a large share of summer AC problems. It's also the easiest thing to fix yourself.
Find your filter size
The size is printed on the edge of the filter you have now, for example 20x25x1. The last number is the thickness in inches. Write it down or take a photo so you buy the right one every time.
Which filter to buy
- MERV 8 pleated: the best fit for most homes. Good dust capture without restricting airflow.
- MERV 11: helpful for allergies or pets. Check it more often, because it loads up faster.
- MERV 13 and up: only if your system is designed for it. Ask a technician, because some systems can't push enough air through.
- Fiberglass: cheap, but it catches very little dust.
How often to change it in the Imperial Valley
| Your home | How often | Note |
|---|---|---|
| Summer, typical home | Every 30–60 days | Check monthly; change when it looks gray. |
| Pets, dusty area or farmland nearby | Every 30 days | Also check after any dust storm. |
| Winter, light use | Every 90 days | Still check it at least once. |
| 4–5 inch media filter | Every 6 months | Thicker filters last longer; check in midsummer. |
Write the install date on the filter's edge with a marker. Next month you'll know at a glance how long it's been in.