Why Cleaning Your Air Conditioner for Winter Is Just as Important as Summer

Why Cleaning Your Air Conditioner for Winter Is Just as Important as Summer

When most people think about cleaning their air conditioner, they picture the lead-up to scorching summer days. But many Australian homeowners don’t realise that your split system needs just as much attention before winter, especially if you’re using it for heating.

Just as you wouldn’t drive your car without servicing it, running your aircon in heating mode without a proper clean can lead to a host of issues from higher power bills to harmful indoor air. Here’s why pre-winter cleaning is essential and what could go wrong if you skip it.

 


 

Your AC Works Differently in Winter

Most modern air conditioners are reverse-cycle systems, meaning they can both cool and heat your home. In winter, your unit doesn’t just blow warm air; it reverses the refrigeration process, absorbing outdoor heat and pushing it inside. This heating cycle:

  • Pulls in cool, often damp outside air
  • Cycles it through internal coils and filters
  • Blows warm air into your living space

If those internal parts are clogged with dust, bacteria or mould, it doesn’t just reduce efficiency it contaminates the air you breathe.

 


 

What Can Go Wrong if You Don’t Clean It?

  • Circulating mould and bacteria
    Warm air blowing through dirty filters and coils spreads harmful particles around your home. This is especially risky in winter when windows are closed and ventilation is limited.
  • Musty smells every time you turn it on
    A stale, “wet sock” odour usually means mould or mildew build-up inside your unit.
  • Higher heating bills
    When filters and coils are grimy, your aircon must work harder to push warm air, leading to longer run times and increased energy use.
  • Dry skin and irritated airways
    Heating dries out the air. Add dust and mould spores, and you have a recipe for itchy skin, sore throats and aggravated allergies.
  • Potential leaks or water damage
    Condensation still forms in heating mode. If drainage lines are blocked by debris or biofilm, water can leak into walls or ceilings, causing hidden mould and structural damage.
  • Strange noises or breakdowns
    Dirt in the fan or blower can cause rattling, humming or clicking sounds—and eventually mechanical failure. You could be left without heating when you need it most.

 


 

What to Clean Before Winter

To keep your unit healthy and efficient, make sure you:

  • Wash or replace filters to maintain proper airflow
  • Remove dust and build-up from evaporator coils
  • Clear drainage lines to prevent condensation leaks
  • Clean the blower fan to avoid noise and maintain airflow balance
  • Apply an anti-mould treatment or use a diffuser to prevent regrowth

Using a dedicated aircon cleaning kit makes each of these steps quick and safe, even if you’ve never done it before.

 


 

The Takeaway: Clean Air = Warm, Healthy Home

Prepping your air conditioner for winter isn’t just about comfort—it’s about health, efficiency and protecting your home. A 30-minute clean now can save you hundreds in repairs and power bills while giving your family clean, warm air all season long.

Ready to clean your aircon? Check out our DIY cleaning kits and anti-mould solutions to make the process easy, even for first-timers.

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