WOLLONGONG MOULD REMOVAL SERVICES
Air Conditioning and Duct Mould Cleaning in Wollongong
If your ducts are the flexible insulated kind and the insulation has gone mouldy, no amount of cleaning will fix it. That duct has to be replaced, and anyone quoting you a clean instead is selling you something that cannot work.
Trusted Air Conditioning Mould Cleaning in The Illawarra, NSW
You notice it about ten seconds after the unit kicks on. That damp, sock-drawer, old-cellar smell, pushed out into the room on the first blast of air. Then it fades, or you stop noticing, until tomorrow morning when it does the same thing again.
That smell is the diagnosis. Air conditioners do not create smells. They move air over a wet surface and blow whatever is growing on that surface into the room.
Here is the mechanism, because it explains why this keeps happening to you and not to your neighbour. A cooling coil works by sitting below the dew point of the air passing over it. That is not a fault, it is the whole design: air hits a cold surface, water condenses out, the room gets drier and cooler. Which means every cooling season your unit runs a permanently wet metal surface in a dark box, with a steady supply of dust and skin cells landing on it. Give that four or five humid Illawarra weeks and you have a colony.
Then the fan blows across it, into the room, all day.
Wollongong Mould Cleaning & Removal has been doing this across the Illawarra for 15 years. He will tell you on the spot whether it is the unit, the ducts, or something else in the house entirely that the air con is just circulating for you. Where the job needs a licensed air conditioning technician to pull a system apart or re-duct it, he organises that and stays the single point of contact.
Sound familiar?
- A musty or sour smell for the first minute every time the system starts
- Black speckling on the plastic louvres, the blades of the barrel fan, or around the vents
- Someone in the house with hay fever or asthma who gets worse when the air con runs
- Water marks or drips below the indoor unit
- Ceiling vents in a ducted system with dark staining around the edges
- A unit that was serviced recently and still smells
The inspection is free, and that includes being told the unit is fine and the smell is coming from somewhere else.
FREE INSPECTION, NO OBLIGATION
We will call you back personally to arrange a time.
Split System or Ducted, Which One Are You Dealing With?
Same organism, two completely different jobs and two very different bills.
Split systems are the wall-mounted units. The mould lives in three places, and only one of them is the bit you have been cleaning. The filters you slide out and rinse are the least of it. Below them sits the evaporator coil, a dense aluminium fin block that is wet every time the unit cools. Behind that is the barrel fan, a long cylinder of small blades that flings air into the room. That fan is usually where the smell actually is, and you cannot reach it by lifting the front cover. A proper clean means the unit comes apart, the coil and fan get chemically cleaned and rinsed into a bagged catch, and the drain tray and line get cleared.
Ducted systems add a whole roof space to the problem. The return air grille, the plenum, the coil in the fan unit, and then tens of metres of duct running through a roof cavity that hits well over 40 degrees on a February arvo. Cold duct, hot humid roof air, and any gap in the insulation gives you condensation on the duct itself.
If the smell is only in one room, start with the unit in that room. If it is every vent in the house at once, the problem is upstream in the fan unit or the return, and cleaning individual vents will not touch it.
Mould in the air con is also worth checking against the rest of the house, because a unit can be the victim rather than the cause. If there is already growth on a ceiling or in a wall cavity, the system will pick up spores and post them to every room. That is covered on ceiling mould removal and wall mould removal, and the mould cleaning hub is the place to start if you have more than one of these at once.
How We Clean Mould Out of Air Conditioning Systems
Free inspection, with the covers off
We open the unit and show you what is on the coil and the fan before quoting anything. On a ducted system that means the return, the fan unit and a look in the roof space at the duct runs. If we cannot show you mould, we will not charge you to remove it.
Find out why it is wet
A blocked condensate drain, a tray sitting out of level, a unit oversized for the room so it short-cycles and never dries its own coil, a crushed or torn duct sweating in the roof. Cleaning without finding this means you are booking us again next summer.
Protect the room, then dismantle
Covers, louvres and the drain pan come off, and the wall and floor below go under a catch bag so the runoff goes into a bucket rather than down your wall. Ducted jobs get the return sealed so nothing gets pushed through the house while we work.
Coil, fan and tray cleaned properly
The coil gets a purpose-made cleaner worked through the fins and rinsed out, not a spray-and-leave. The barrel fan is cleaned blade by blade, which is slow and is the difference between a clean that holds and one that smells again in a fortnight. Drain line flushed and checked for fall.
Ducts assessed honestly, cleaned or replaced
Hard ducting and the metal parts of the system get cleaned and HEPA vacuumed. Flexible insulated duct with mould in the insulation gets quoted for replacement, because that is the only thing that works. More on that below.
Dry it, and set it up not to do it again
Run the system on fan for long enough to dry the coil, check the drain runs, and set out what to change so it stays clean. Our mould prevention page covers the ongoing side.
Want this walked through for your place? Call (02) 4093 0541.
Why a Duct Clean Cannot Fix Mouldy Duct Insulation
This is the part the quotes do not mention, and it is the reason some people pay for duct cleaning twice.
Most Australian ducted systems do not use rigid metal ducting. They use flexible duct: a plastic inner sleeve wound on a wire spiral, wrapped in a sleeve of fibrous insulation, wrapped again in an outer skin. That insulation layer is soft, porous and fibrous, and it sits in a roof space that is hot and humid for months at a time while the duct inside it runs cold.
The US Environmental Protection Agency puts it about as plainly as a government agency can. In its guidance on whether to have home air ducts cleaned, the EPA says that if you have insulated air ducts and the insulation gets wet or mouldy, “it cannot be effectively cleaned and should be removed and replaced.”
Not cleaned harder. Not fogged. Replaced! Which is damn expensive..
The same EPA guidance is worth reading before you accept any duct quote, because it says two other things the industry does not put in its ads. First, duct cleaning “has never been shown to actually prevent health problems,” so a routine annual duct clean sold on health grounds is being sold on a claim the EPA does not support. The reason to clean is visible mould, vermin, or debris actually blowing out of your registers. Second, and this is the one that saves you the second bill: “if the conditions causing the mould growth in the first place are not corrected, mould growth will recur.”
The EPA also gives you a question to ask, and we would rather you asked it of us too. Many parts of a system cannot be seen without dismantling it, so if a company tells you there is mould in there, ask them to show it to you. A phone photo of your own coil is a reasonable thing to expect before you spend money.
So the honest version, which admittedly costs us work.
If the mould is on the coil, the fan, the tray, the grilles or inside hard metal ducting, cleaning is the right answer and it holds as long as we fix why it was wet. If it is in the insulation of flexible duct, cleaning is theatre. That run gets replaced, and on a system with widespread contamination you are looking at a re-duct rather than a clean, which is a licensed air conditioning job we coordinate rather than a cleaning job.
And if the coil is spotless and the smell turns out to be a wet wall cavity that the system is simply broadcasting, we will tell you that and quote the actual problem instead.
Musty Smells, Ceiling Vents and Wall Cavities: Where the Odour Is Really Coming From
A musty smell that arrives with the air con is not always the air con. Before you spend money on the system, it is worth ruling out the other sources, because the air handler is very good at taking a small problem in one part of the house and distributing it evenly through the rest.
- If the smell is strongest in the bathroom and the fan vents into the roof rather than outside, the roof space is getting the moisture and the system is collecting it, which is covered on bathroom mould removal.
- If there is dark staining spreading out from a ceiling vent, the moisture is usually in the roof space rather than the duct, and ceiling mould removal explains how to tell the two apart.
- If the smell rises from the floor rather than the vents, particularly in a timber-floored home, look under the house first at subfloor and mouldy floor treatment.
- If it is worse after rain, there is water getting in somewhere and leaking roof water damage is the place to start.
- If growth is already through wall or ceiling linings, cleaning the air con will not stop it recirculating and it needs structural mould remediation.
- If this is an office, a shop or a strata building where the system is shared, the responsibility and documentation side sits on commercial mould remediation.
How Much Does Air Conditioning Mould Cleaning Cost?
The inspection is free, and if the answer is that you can sort it yourself with a rinse and a fan cycle, that is what we will tell you.
| Job | What it covers | Cost |
|---|---|---|
| On-site inspection | Covers off, coil and fan shown to you, honest answer on whether you need us | Free |
| DIY | Filters rinsed and dried, louvres wiped, fan-only cycle after cooling to dry the coil. If the smell goes and stays gone, you are done | $0 |
| Split system, single head | Unit dismantled, coil and barrel fan cleaned, tray and drain line cleared, surfaces treated | $250 to $450 |
| Multi-head or multiple units | Same again per head, usually with a discount after the first | $500 to $1,000 |
| Ducted system clean | Return, plenum, fan unit and coil cleaned, hard ducting and registers HEPA vacuumed, roof-space duct runs assessed | $800 to $2,000 |
| Flexible duct replacement | Mouldy insulated duct runs removed and replaced. Priced per run by a licensed air conditioning technician, coordinated by us | Quoted with the job |
These are current Illawarra market rates for scoping purposes. Your exact figure comes from the free inspection.
What moves the price is access and head count more than anything else. A unit over a stairwell, a ducted fan unit in a tight roof space with no walkway, or a system where the drain has to be re-run all add time. Older units cost more to clean properly because the plastics have gone brittle and come apart slowly.
One thing worth knowing before you book anyone: a standard air conditioning service is not a mould clean. A service checks gas pressure, electricals and airflow, and usually rinses the filters. It does not pull the barrel fan and clean it. If you have been getting the unit serviced yearly and it still smells, that is why.
How Our Local Illawarra Knowledge Changes the Job
Coastal humidity is the whole story here, and it is why air con mould is a bigger deal in Wollongong than it is an hour inland.
Through summer the air coming off the water sits heavy for weeks at a time. Your unit is pulling that air across a cold coil for eight hours a day, which means it condenses far more water than the same unit would in a drier climate, and the coil almost never gets a chance to dry out between runs. Homes closer to the beach through Thirroul, Austinmer, Corrimal, Fairy Meadow and down at Shellharbour also get salt in the air, which sits on the aluminium fins and holds moisture against the metal.
The roof spaces matter too. A lot of the brick veneer stock through Figtree, Unanderra, Dapto and Albion Park has ducted systems retrofitted into roof cavities that were never designed to carry them, so duct runs get squashed against rafters, insulation gets compressed or torn on installation, and that is exactly where the condensation shows up years later.
Practical upshot: in this climate a unit that gets a fan-only run after cooling, and a clean when it needs one rather than on a calendar, will go years without smelling. One that gets neither will be back to square one by the following February.
We work the whole Illawarra: Wollongong and the northern suburbs, Port Kembla, Unanderra, Dapto, Albion Park, Shellharbour and down to Kiama.
Get Your Free Air Con Inspection Today
Free on-site inspection, covers off, and we show you what is actually in there before you spend anything.
Call Wollongong Mould Cleaning on (02) 4093 0541.
Frequently Asked Questions
Why does my air conditioner smell musty when it starts?
Because the first blast of air pushes the smell off a wet surface inside the unit before the airflow dilutes it.
The cooling coil sits below dew point by design, so it is wet whenever the unit cools, and mould grows on the coil, the drain tray and the barrel fan behind it.
If the smell fades after a minute and returns at every start-up, that is the signature.
Is mould in the air conditioner making us sick?
For most people, no.
NSW Health states that most people will not experience health problems from contact with mould and that everyone breathes in mould spores, while people with asthma, allergies, weakened immune systems or chronic lung disease can be more sensitive. What is different about an air conditioner is distribution rather than danger: the system takes growth in one small box and moves it through every room. If someone in the house is unwell, see a doctor about the symptoms while we deal with the unit.
Can I clean the mould out of my air conditioner myself?
The filters, yes, and you should.
Slide them out, rinse them, dry them completely before they go back. What you cannot reach is the coil behind the filters and the barrel fan behind that, which is where the smell usually lives.
If rinsing the filters fixes it and it stays fixed, you have just saved yourself a bill. If the smell is back within a fortnight, the problem is deeper in the unit.
Should I get my ducts cleaned every year?
The EPA does not recommend routine duct cleaning, and says duct cleaning has never been shown to prevent health problems.
Its advice is to clean when there is visible mould growth, vermin, or debris actually being released from the registers. An annual duct clean sold on health grounds is being sold on a claim the EPA does not support.
My ducts are mouldy. Can they be cleaned?
Hard metal ducting can be cleaned.
Flexible insulated duct cannot, once the insulation itself is wet or mouldy, and the EPA is explicit that it should be removed and replaced.
Most Australian homes have the flexible type, so ask which you have before accepting a cleaning quote.
How long does an air con mould clean take?
A single split system is usually two to three hours done properly, most of it on the barrel fan.
Multi-head systems run half a day to a day depending on head count and access.
Ducted systems are typically a full day, longer if duct runs need replacing, which gets scheduled separately with the air conditioning technician.
Will the smell come back?
Only if the coil stays wet between runs.
The single most useful habit is running the system on fan-only for fifteen to twenty minutes after you finish cooling, which dries the coil before the unit sits idle.
Many units have a dry or self-clean function that does this automatically and most people have never turned it on. Fix a blocked drain or a sweating duct at the same time and a clean will hold for years.