In short: do three things before the first hot week. Rinse the filters yourself, clear the leaves and growth away from the outdoor unit, then run the system on cold for twenty minutes and pay attention to what it does. If it smells musty, takes noticeably longer to cool than last summer, drips, or rattles, book a clean now rather than in December — that is the difference between a week’s wait and a month’s.
Step one: rinse the filters
Ten minutes, no tools, and it is the single most useful thing you can do yourself. Lift the front cover of the indoor unit, slide out the two mesh filters, rinse them under a tap from the clean side outwards, let them dry properly before they go back in. A wet filter put back wet is how you create the smell you are trying to avoid.
If the filters come out grey and matted rather than dusty, that is a signal about what is further inside — the coils and the fan barrel behind them have been catching whatever got past.
Step two: clear the outdoor unit
The outdoor unit rejects the heat your indoor unit collects, and it cannot do that if it is packed with leaves or boxed in by growth. Before summer:
- Clear leaves, seed pods and cobwebs from the fins and the fan guard
- Cut back anything growing within about half a metre on the sides and above
- Move whatever has been stored against it over winter — bikes, bins, pot plants
- Check it is sitting level and that the bracket or feet have not corroded through
Hose the fins gently from outside in if they are visibly dirty, with the power off at the isolator. Do not use a pressure washer on them — the fins bend and once bent they stay bent.
Step three: the twenty-minute test run
This is the part most people skip, and it is the part that tells you whether you need us. Set it to cool, put it on a low temperature, and leave it running for twenty minutes. Then note five things:
- Smell. Anything musty in the first minute is the airflow crossing something growing inside. It does not clear, you just stop noticing.
- Airflow. Hold your hand at the vent. Weaker than you remember, with clean filters, means the restriction is further in.
- Time to cool. If the room takes noticeably longer than it did last summer, something has changed.
- Water. Drips inside, or damp on the wall under the unit, usually means a blocked drain line rather than a leak.
- Noise. A rattle or a scrape that was not there before is worth investigating before you run it hard for three months.
What each symptom usually means
- Musty smell, normal airflow — mould and grime on the fan barrel and coils. A deep clean is the fix.
- Weak airflow, clean filters — buildup on the coil fins and in the barrel slots. Also a clean.
- Dripping inside — blocked drain line or a drip tray full of sludge. Part of a clean.
- Grinding, ice on the coil, breaker tripping, no cold air at all — not a cleaning job. That is a refrigeration technician, and we will tell you so rather than take the booking.
Why now and not the first hot week
Everyone calls on the same three days. The first genuine heatwave is when people switch the aircon on, discover it smells or does not cool, and start ringing around — and that is when lead times across the whole trade stretch out. A clean booked in spring happens on a day that suits you. The same clean booked in a December heatwave happens when someone has a slot.
There is also a practical reason: if the test run turns up a fault rather than dirt, you want to find that out while there is still time to get it repaired before you actually need the thing.
What a pre-summer deep clean covers
Not a filter wipe. The indoor unit comes apart — cover, louvres, drip tray — and the parts you cannot otherwise reach get treated: coil fins, fan barrel, drip tray, drain line. Eco-friendly degreaser, a pressure rinse into a catch bag so nothing lands in the room, then sanitising. Drop sheets down, vacuum running, and photos of what came out if you want them.
- Split system deep clean — $249 + GST
- Ducted system deep clean — $350 + GST
- Outdoor condenser unit — $149 + GST
- 20% off your second unit on the same visit
If you are weighing up whether it is worth it at all, we went through that honestly in is aircon cleaning worth it, including the cases where it is not.
Ducted systems before summer
A ducted system has more places for a summer to go wrong. Before the season, walk the house and check every outlet is actually delivering air — it is common to find one room that has quietly stopped. Look at the return-air grille, which is where all the dust in the house gets pulled through, and check the filter behind it. If a room was noticeably worse than the rest last summer, say so when you book, because that changes what we look at.
If you have pets
Pet hair and dander load a system faster than anything else in a normal house, and it binds to the coil rather than sitting loose on the filter. If you have a shedding dog or cat, rinse the filters monthly through summer rather than seasonally, and expect the annual clean to be a genuine annual rather than a nice-to-have.
What we actually find after a Sydney winter
A split system that sat idle from April to September is not clean just because it was not running. Three things happen over a Sydney winter:
- The drip tray dries out with sludge in it. Whatever was in suspension at the end of last summer settles and sets. That is the first thing to block the drain line when you switch back to cooling.
- Humidity keeps working on the barrel. Sydney does not get a dry winter. The fan barrel and the coil stay damp enough, often enough, that growth carries on quietly through the cold months with no airflow to disturb it.
- Spring loads the filters fast. The unit comes back on right as pollen and seed fluff peak, so a filter that looked acceptable in August is packed by October.
That combination is why a unit can smell worse on the first hot day than it did on the last hot day of the previous summer, even though nobody touched it in between.
How often, after this one
Once a year suits most Sydney homes, and doing it in spring means the clean lands right before the hardest three months. Every six months is more realistic if you have pets, if someone in the house reacts to the air, or if the system runs most of the year. The full reasoning is in how often you should clean your air conditioner, and there is a price breakdown in how much aircon cleaning costs in Sydney.
Getting it booked
We work across Sydney metro, seven days a week, 7:00am to 7:00pm, which means a clean can go in on a Saturday if that is what works. Fixed price before we start. Call 0483 928 714 or request a quote and tell us what the test run turned up — it helps us bring the right thing.
More on the service: air conditioner cleaning, split system cleaning and outdoor condenser service.
Frequently asked questions
When should I get my aircon serviced before summer?
Spring, before the first hot week. A clean booked in September or October happens on a day that suits you; the same clean booked during a December heatwave happens whenever a slot opens, because that is when everyone calls at once.
What can I do myself to prepare my aircon for summer?
Rinse the mesh filters and let them dry fully, clear leaves and growth from around the outdoor unit, and run the system on cold for twenty minutes to check the smell, the airflow, how long it takes to cool, whether it drips and whether it makes a new noise.
Why does my air conditioner smell when I turn it on for summer?
Because the airflow is crossing mould and grime that built up on the fan barrel and coils while the unit sat idle. Nothing sprayed into the vents reaches the barrel, which is where the smell comes from. A deep clean removes it rather than masking it.
How long does a pre-summer aircon clean take?
Allow around an hour and a half for a single split system, including setting up drop sheets and putting the unit back together properly. Multiple units on the same visit take less time each.
Should I clean the outdoor unit too?
Clear the leaves and growth around it yourself before summer. A full outdoor condenser clean is $149 + GST and is worth doing with the indoor clean if the unit sits under trees or has not been touched in a few years.
