How Often Should You Replace Filters? Advice for Pet Owners & Allergy Sufferers

When you live with pets or have family members sensitive to allergens, maintaining clean, breathable air inside your home becomes more than a comfort—it’s necessary. One often-overlooked aspect of indoor air quality is the condition of your air conditioning filter. Whether you're enjoying the summer breeze through your ducted system or running your split system daily during cooler months, that filter constantly catches dust, hair and allergens. But how often should AC filters be changed? The answer depends on key household factors, particularly pets and respiratory conditions.



This blog is a practical guide for homeowners, particularly those with furry or feathered companions or family members affected by asthma or hay fever. It offers valuable air filter tips for pet owners and highlights how regular filter replacement supports efficient air conditioning and a healthier home environment.

Why Filter Replacement Frequency Varies for Homes with Pets

Pets bring warmth and companionship into our lives and introduce dander, hair, and dirt into the indoor environment. These particles quickly accumulate on AC filters, reducing their ability to trap airborne pollutants.

Homes with multiple or high-shedding animals may need more frequent filter changes than the average household. If your filters clog up every few weeks, it could be due to your four-legged friends.

• Cats and dogs shed hair and skin cells that easily clog filters
• Birds produce feather dust that can settle into ducted systems
• Long-haired pets create heavier loads on intake filters, especially in summer

If you’ve got a dog that enjoys naps near the AC vent or a parrot with free rein of your living space, your system works overtime to maintain healthy air. Check filters monthly and consider changing them every 1–2 months if you see visible dirt.

Allergy Sufferers: How Clean Filters Reduce Symptoms

For allergy sufferers, clean air isn’t just a comfort—it’s a health necessity. Filters trap airborne irritants like pollen, dust mites, and mould spores, common triggers for asthma and hay fever.

When filters become saturated with particles, they can no longer prevent these irritants from circulating through your home. This can lead to itchy eyes, sneezing fits, and disrupted sleep, particularly during allergy seasons.

Signs You Need a New Filter:

• Increased sneezing or coughing indoors
• Dust builds up on surfaces despite regular cleaning
• A musty smell when the AC runs

Regular filter changes—every 6 to 8 weeks during peak pollen months—can significantly reduce indoor allergen levels and make your home more comfortable for sensitive family members.

The Hidden Costs of Neglecting Filter Changes

Forgetting to change your AC filter might not seem like a big deal, but over time, it can impact everything from your power bills to your air conditioning system’s lifespan. A clogged filter reduces airflow, making the unit work harder and drawing more energy.

The consequences go beyond energy efficiency:

• Higher electricity bills due to restricted airflow
• Shortened system lifespan due to motor strain
• Increased indoor humidity and poor air circulation

Neglected filters also cause dirty ducts and can turn your cooling system into a breeding ground for mould, especially concerning for those with respiratory issues.

Seasonal Guidelines for Replacing Air Filters

Air conditioning systems must adapt to shifting indoor air quality demands throughout the year in locations with changing seasons and fluctuating humidity, such as coastal areas. Aligning your filter replacement schedule with these seasonal changes is one of the easiest ways to maintain a cleaner, more efficient system all year round.

• Summer: Replace monthly, especially during peak cooling periods
• Autumn: Clean or change as allergens settle indoors
• Winter: Replace every 2 months if using reverse-cycle heating
• Spring: Replace monthly to tackle high pollen levels

These timelines should be adjusted if you have pets, household members with respiratory sensitivities, or if the system runs heavily during heat waves or cold snaps. More frequent checks and changes can make a noticeable difference to your comfort and air quality.

Signs Your AC Filter Needs Immediate Replacement

Sometimes, the filter will let you know it’s past its prime—even if you’ve lost track of your calendar. Keep an eye (and nose) out for the following signs.

• Noticeable dust around vents or on surfaces
• Reduced airflow from your AC unit
• Musty odours when the unit is running
• Increased allergy symptoms indoors

If you remove the filter and it’s grey or covered in visible grime, replace it immediately—even if it hasn’t reached the recommended time frame.

DIY Filter Checks vs Professional Air Conditioning Services

Some filter maintenance is straightforward—many filters are accessible behind a panel or grille and slide out easily. You can check and replace them yourself with little fuss.

However, there are situations where a professional should be called:

When to Call in the Pros:

• You’re unsure how to access or replace your filter
• Your system has unusual noise or odours
• There’s inconsistent cooling or frequent cycling

Technicians can also clean internal components, check refrigerant levels, and recommend filters that meet your specific indoor air needs. This is especially useful if pets or allergies are involved.

Simple Maintenance Tips to Extend Filter Lifespan

Want to get the most out of each filter and keep your system running efficiently? A few simple habits can help extend the time between changes while supporting better air quality.

• Vacuum air vents regularly to reduce debris intake
• Groom pets weekly to minimise indoor shedding
• Use an air purifier to complement AC filtration
• Set calendar reminders for monthly filter inspections

Incorporating these steps into your home routine ensures your air conditioning runs cleanly and economically year-round.

Keep Your Air Clean & Efficient with Us

At Airdale Services, we understand how clean indoor air affects your health, comfort, and energy usage, especially for families with pets or allergies. Our team offers expert air conditioning services in Wollongong, including filter replacement, system maintenance, and tailored advice to suit your home’s needs.

If it’s been a while since you’ve checked your filters or noticed allergy flare-ups or poor airflow, we’re here to help. Call us to book a consultation. Let us help you breathe easier in your home.