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How Often Should You Replace Home Air Filters?

Don’t panic, but if you only change your air filters once a year, there’s a problem. A dirty, dangerous, and potentially expensive problem.

So… how often should you replace home air filters? Manufacturers recommend changing your home air filters at least every 30 days. Some folks swear that you only need to replace them seasonally. The discrepancy boils down to the fact that you need to change filters whenever they’re dirty—and that varies.

Be Safe and Change Air Filters Monthly

To protect yourself and your HVAC system, we recommend changing air filters or cleaning a reusable filter every 30 days. Waiting longer makes it more likely you’ll forget.

Seem like too much? Keep these tips in mind:

  • Thicker, pleated filters last longer than thin fiberglass ones.
  • Buy in bulk for the best price. Store them somewhere dry.
  • If the used filter still looks clean, wait one week and check again.

You might find that your home only needs a new air filter every 45 or 60 days. Whatever the case may be, err on the side of caution. Mark your calendar or set a recurring reminder on your phone to stay on schedule.

Air Filters Protect You & Your Equipment

Clean filters don’t just keep bacteria and dust out of your lungs; they also keep your heating and air conditioning systems running smoothly. HVAC units must work harder when they’re “breathing” through a dirty filter.

When HVAC units work harder, you waste money on utilities and there’s more wear and tear. You could wind up with a frozen coil or burnt-out motor. Pinching pennies on air filters could result in a thousand-dollar repair later.

Why is My Air Filter Always Dirty?

Air filters contend with whatever’s inside the home, including:

  • Pet dander
  • Pollen
  • Dust mites
  • Mold spores
  • Cigarette smoke
  • Cooking fumes
  • And other microscopic intruders

Look for HEPA or “electrostatic” filters that trap more dirt and last longer. The economy-grade filters only block large particles, and they get caked with dust quickly.

If you have poor indoor air quality—especially if there’s asthma or allergies in the household—consider a whole-home air filter for stronger protection.

Remember Seasonal HVAC Maintenance, Too

With regularly changed air filters, your furnace, heat pump, and AC should all work efficiently for an entire year. Get everything inspected and tuned up by an HVAC professional to prolong your equipment and lower your bills.

We recommend a full AC cleaning every spring and a furnace tune-up or heat pump maintenance visit in the fall. We’ll clean the interior parts, lubricate bearings, and inspect gas valves, and more.

For HVAC maintenance in Fenton, MO and the surrounding St. Louis area, contact us at Metro Heating & Cooling and enjoy friendly, affordable, expert service.

Frequently Asked Questions:

Q1: How do I know when my home air filter needs to be replaced?
A: Check your air filter every 30 days. If it looks dirty or clogged, it’s time to replace it. Thicker filters may last up to 60 days.
Q2: What happens if I don’t change my air filter?
A: A clogged filter can strain your HVAC system, reduce efficiency, increase energy costs, and cause costly breakdowns.
Q3: Are pleated filters better than fiberglass filters?
A: Yes, pleated filters last longer and trap smaller particles, offering better protection for your home’s air quality and HVAC equipment.
Q4: Can poor indoor air quality make my filters dirtier faster?
A: Absolutely. Pet dander, pollen, smoke, and other contaminants can cause your filters to clog more quickly and require more frequent replacement.

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