Does a deep aircon clean help during the haze in Singapore?
An aircon does not filter haze: its mesh filter stops dust and hair, not the fine particles in haze. What a deep clean does is stop a dirty coil and blower fan from blowing dust and mould back into a closed room, which matters most when windows stay shut. Pair it with an air purifier.
Key takeaways
- The aircon recirculates the room's air: with windows shut, whatever sits on the coil and blower fan is blown around all day.
- Haze months are dirtier months: Uncle Eric told The Straits Times that blower fans and filters are coming in much dirtier than usual.
- A clean unit and a purifier do different jobs: the clean stops the aircon adding dust and mould, the purifier removes the haze particles.
- Our cleaners are low-odour: Viper Heavy Duty is described by its maker as non-toxic, and it is NSF-registered for use around food.
The video above is a real job: a smelly Mitsubishi Electric Starmex wall unit. Under the cleaning foam, the coil is streaked black with mould, the blower fan comes out coated in dust, and after the PowerJet wash the water in the wash bag is dark and muddy. That is what a family breathes past every time the unit runs.
Why the haze makes a dirty aircon worse
During the haze, NEA's advice is to keep windows and doors closed when the air is bad. So the aircon runs longer, often day and night, and it only ever moves the air that is already in the room.
Three things happen in a Singapore home at the same time:
- More hours of use. The coil stays cold and wet for longer, and in our humidity it hardly dries out.
- Mould grows on the wet coil and blower fan. Dust that slips past the filter sticks to the damp fins and feeds it.
- The same air goes round and round. Spores and dust knocked loose from the blower fan go straight back into the closed room.
In October 2026, Uncle Eric told The Straits Times that demand for servicing had risen by 15 to 20%, and that most units were coming in with blower fans and filters much dirtier than usual. Many of our customers are on quarterly maintenance, so we see the build-up from visit to visit.
What a deep clean does, and what it does not do
| Deep aircon clean | Air purifier |
|---|---|---|
Removes mould and slime from the coil and blower fan | Yes | No |
Stops the aircon blowing dust and musty smells into the room | Yes | Partly |
Removes fine haze particles from the room's air | No | Yes, with a HEPA filter |
Helps cooling and airflow | Yes | No |
So the two work together. A clean aircon stops adding to the problem; a purifier with a HEPA filter takes the haze out of the room. Uncle Eric's air purifier picks for the haze cover what to look for.
A mother's feedback after the haze
One of the homes Evan washed during this haze was a family whose children had been coughing badly since the haze began. The mother, who asked not to be named, told us afterwards that the children were much better within a week of the PowerJet wash with Viper Heavy Duty. Evan's photo from that job appeared in The Straits Times.
That is her experience, not a medical promise. A clean aircon removes one source of dust and mould in a closed room; anyone whose cough does not ease should see a doctor.
Which cleaners we use, for sensitive noses
People with sensitive noses, sinus trouble or asthma often worry about the chemical smell after a service. We use two cleaners from Refrigeration Technologies:
- Viper Heavy Duty for dirty coils. The maker describes it as non-toxic, with no odours, and it carries an NSF registration for use around food. Its safety data sheet is public.
- Venom Pack Evaporator, an enzyme coil cleaner for a severe smell. It is a concentrate we dilute on site, so we can make it stronger for the worst cases. Its enzymes break down the bacteria that cause the smell, and the maker rates it safe on aluminium coils.
Whichever one goes on the coil, the PowerJet flushes it out of the fins afterwards. Strong alkaline cleaners are kept for extreme cases only. More on this in when a very dirty coil needs the heavy-duty cleaner.
What it costs
Your home | What we usually advise | Price |
|---|---|---|
1 aircon | Chemical wash: coil chemical, then PowerJet on the coil, blower fan and drain pan | S$120 per unit |
2 aircons or more | PowerJet deep clean with Viper Heavy Duty, or the enzyme cleaner for a bad smell | S$80 per unit |
2 aircons or more, lighter dirt | General servicing with the PowerJet wash on the coil added | S$30 per unit add-on |
For a single unit, premium servicing plus the coil cleaner add-on comes close to the chemical wash price, so the chemical wash is the better deal. The technician looks at the coil first and tells you which one it needs before starting. Every service has a 90-day warranty. See all options on our premium servicing page.
Keeping the air cleaner until the haze clears
- Keep windows shut on bad days and check NEA's daily readings.
- Wash the aircon filters every two weeks while the haze lasts.
- Run fan mode for 15 to 30 minutes before switching off so the coil dries.
- Run an air purifier in the rooms you sleep in.
- Book a deep clean if the aircon smells musty or the vents look dark. If a musty smell is the main problem, read why an aircon smells.
Book online in under a minute, or ask Luna, our AI assistant, on WhatsApp at any hour.
Frequently asked questions
Does a home aircon filter out haze?
No. The mesh filter in a wall-mounted aircon catches dust and hair, not the fine particles in haze. An air purifier with a HEPA filter is what removes those from a room.
Should I open the windows to air out the room during the haze?
When the haze is bad, keep windows and doors closed and follow NEA's health advisories. A clean aircon and an air purifier then keep the closed room comfortable.
Is the cleaner you use safe for children and people with sensitive noses?
The maker describes Viper Heavy Duty as non-toxic with no odour, and it is NSF-registered for use around food. We flush it out of the coil with the PowerJet, and the maker's data sheets are linked in this guide.
Will a deep clean stop my child's cough?
We cannot promise that. A clean aircon stops a dirty coil and blower fan from adding dust and mould to the room, which some customers notice quickly. A cough that does not ease needs a doctor.
How often should I service my aircon during a long haze?
If your aircon runs most of the day, every 3 months keeps the coil and blower fan from building up. Many of our customers are on quarterly maintenance for this reason.
Eric Lim, aka Uncle EricFounder of iAircon.Repair, now in its 10th year servicing aircons in Singapore. Some of our jobs are filmed, and you can watch the work on YouTube.
