How do I clean my split system filters?

Turn the unit off at the remote and, if your manual says to, at its circuit breaker too. From a stable step, lift the front panel by its sides until it stays up. The filters are fine mesh panels, usually two side by side, that slide down and out. Note which way round they go.

Vacuum the dusty side gently with a brush attachment. If they need more, rinse them from the clean side so the water pushes dust back out the way it came in, using lukewarm water and a little mild detergent. Shake off the water, let them dry completely in the shade, slide them back in the right way round and close the panel. Running the unit with wet or missing filters sends moisture and dust onto the coil.

The Victorian Government suggests about twice a year, or more often if the unit is used a lot. It's worth checking them every few weeks in the busy months of summer and winter, and more often with pets, a smoker in the house, or a new estate with building sites nearby. Dirty filters significantly cut airflow and efficiency, so a quick look pays off.

Avoid hot water, scrubbing brushes, the dishwasher and drying filters in direct sun, which can warp the frames or tear the mesh. Some units also have thin extra filters for odours or fine particles. Those are usually replaced rather than washed, so check the manual. Don't spray cleaner into the unit itself.

Filters catch the larger dust. Fine dust, grease and mould still build up on the coil, the fan barrel and in the drain tray, which you can't reach without taking covers off near live parts. If you see black specks, notice a musty smell or the airflow stays weak with clean filters, it's time for a full service that cleans those parts properly and checks the drain and the outdoor unit.