Invisible Mould & Hidden Nasties: How Often Should You Really Clean Your Aircon?

Let’s be honest, most of us don’t give our air conditioning unit much thought until it starts blowing hot air during a Queensland summer. But the real issue might not be what you can see, it’s what’s quietly lurking out of sight. Just because you don’t spot the gunk or smell anything funky doesn’t mean your unit’s in the clear. Mould, bacteria, dust, and who-knows-what can thrive behind those vents, silently messing with your air quality, your lungs, and your power bill.

So... How Often Should You Clean It?

The short answer? At least once a year. The longer answer? It depends on your lifestyle. Your allergies, your pets, and how hard your system works. If your aircon’s clocking overtime through summer and winter, or you’ve got kids, pets, or sensitive lungs at home, then twice a year is your safest bet.

Think of it like a dental clean. Just because everything looks fine doesn’t mean it’s not a breeding ground for trouble. And when it comes to mould, you’ll want to get ahead of it, long before things start to smell funky or look slimy.

What Happens If You Don’t?

Besides the horror of knowing there could be microscopic fungi floating through your living room, dirty air conditioners are big-time energy suckers. A system clogged with grime has to work harder to push out cool or warm air, which means your electricity bill creeps up while your air quality nosedives.

Then there’s the sniffly side of things. Dust, mould, pollen, and bacteria recirculating through your home can trigger allergies, flare up asthma, and give you that lingering “why do I always feel stuffy?” feeling.

Leave it too long and your aircon might not just struggle, it might give up entirely. Neglected maintenance wears out internal parts faster, turning what could’ve been a simple clean into a full-blown replacement.

How Do You Know It’s Time?

If the air smells musty when the unit kicks in, you’re sneezing more than usual, or you spot mould building up around the vents, you’ve probably already left it too long. But even without obvious signs, scheduling regular cleans like brushing your aircon’s teeth is one of the best preventative habits you can adopt. And way cheaper than repairing or replacing the whole unit down the track.

The Bottom Line

Your aircon does more than just keep you cool. It filters the air you breathe, every single day. Whether you're allergy-prone or just not keen on the idea of inhaling mouldy mist, regular cleaning isn’t just maintenance, it’s a health and lifestyle upgrade.

So don’t wait for a weird smell, a spike in your power bill, or a full-blown sneeze-fest to take action. Clean your aircon at least once a year, more if it’s running hard or you’ve got little ones, pets, or sensitive noses in the house. And when you do, make sure it’s a proper clean. Because mould might be invisible, but the consequences of ignoring it? Not so muc