Portable Aircon and Haze in Singapore: Does It Clean the Air?

By Charles, owner and founder of Coolah!

When the haze rolls in, my WhatsApp gets busy. Windows are shut, the room gets stuffy, and the same question keeps coming up: “Charles, will a portable aircon help with the haze?”

Short answer: yes, it helps. But it’s not the whole answer. Let me explain properly, so you can make the right call for your home.

Does a portable aircon clean the air?

Yes, partly. A portable aircon pulls in your room’s air, passes it through its filter, cools it and blows it back out. So the air it circulates does get filtered.

But be clear on what that filter is for. A standard aircon filter is made to catch dust and larger particles. It is not a HEPA filter. The really fine particles in haze, the PM2.5 that NEA reports on, are much smaller. A HEPA air purifier is the machine built for that job.

So here’s my honest answer:

• Portable aircon: keeps you cool with the windows closed, and filters dust and larger particles from the air it circulates.
• HEPA air purifier: better for fine PM2.5.
• When the PSI is unhealthy: use both.

One more thing. During haze, the aircon filter collects dust faster, so it needs cleaning more often. I’ll show you how below.

Check the PSI first

NEA publishes the 24-hour PSI and 1-hour PM2.5 readings on its haze.gov.sg site. Based on NEA’s bands, a 24-hour PSI of 0–50 is Good, 51–100 is Moderate, 101–200 is Unhealthy, 201–300 is Very Unhealthy, and above 300 is Hazardous.

NEA’s health advisory gives different guidance for healthy persons; the elderly, pregnant women and children; and persons with chronic lung or heart disease.

I’m an aircon guy, not a doctor. So please check NEA’s latest advisory and follow official health advice, especially if you have vulnerable family members at home. If someone isn’t feeling well, see a doctor.

Aircon as an air purifier in Singapore? The best setup is both

A portable aircon and an air purifier do different jobs, and they work best together.

During haze, you want your windows and doors closed. But in Singapore weather, a closed room heats up fast. That’s where the portable aircon comes in. It keeps the room cool, so nobody is tempted to open the window “for some air”.

The air purifier then works on the fine particles inside that closed room. Together, you get a room that stays cool, with air being filtered for both larger dust and fine particles.

My tip: put both in the room you actually sleep or work in, and keep that door closed.

No air purifier? Your portable aircon still helps

Not everyone has a purifier at home. Your portable aircon still does useful work:

• It lets you keep the windows closed and stay comfortable.
• Its filter catches dust and larger particles as it recirculates the room’s air.
• The hot air from cooling is vented outside through the exhaust hose, so the room stays cool without opening any windows.

I want to be straight about one thing. The exhaust hose is there to vent hot air. It does not suck haze out of your room. If anyone tells you otherwise, they’re overselling.

How I tell my customers to care for Model A’s filter during haze

Our Coolah! Model A portable aircon is my own design, and its filter is washable. During haze, that filter works harder, so give it more attention. My main tip surprises some people: vacuum it, don’t scrub it.

How often to check and clean

In normal times, a monthly clean is usually enough. During haze, check the filter every few days. While the PSI stays high, clean it at least once a week. If you see a thick layer of dust building up, don’t wait.

A clogged filter also blocks airflow, so the room won’t feel as cold as it should.

Weekly routine: vacuum it

1. Switch off and unplug. Always do this first.
2. Remove the filter gently.
3. Vacuum the dust off gently. Don’t press hard on the mesh.
4. Refit the filter, then switch on.

That’s it. It takes a few minutes, once a week.

It doesn’t have to look brand new

Here’s something I’ve learned from looking after a lot of these machines. A filter doesn’t have to look spotless to work well. In my experience, a light layer of collected dust actually helps it catch more dust. So I just vacuum off the heavy build-up. There’s no need to scrub it clean every single time.

Once in a while: a proper wash

Every now and then, or if the filter feels greasy (for example, near the kitchen), give it a deep clean:

1. Switch off, unplug and remove the filter.
2. Rinse with plain water. If it’s greasy, use a little mild soap, then rinse well.
3. No hot water, no hard brushes. They can warp or tear the mesh.
4. Dry it fully in the shade. Not in direct sun. It must be completely dry before it goes back in.
5. Refit the filter, then switch on.

And please, never run the aircon without the filter, not even “just for a while”. Without it, dust goes straight into the machine.

Haze indoor air tips: seal your window kit

Your window setup matters as much as the filter. Every gap around the exhaust panel is a gap for haze to come in.

• Close the gaps. Seal around the window panel or sliding window with the kit’s seal, or use foam tape for small gaps.
• Keep the hose short and straight. Don’t over-extend it or let it kink.
• Close other windows and doors in the room, and keep the room door shut.
• Re-check the seal whenever the unit or panel has been moved.

Every Model A package comes with a window seal kit, and when I set up, I seal the window for you, with our board where applicable. Staying in an HDB flat with corridor security windows? See how we handle an HDB corridor window panel setup.

Need a portable aircon for the haze?

If the haze is coming and your room is getting stuffy, you can rent a unit. Take a look at our portable aircon rental plans. If you’d rather keep one for good, ask me about Model A’s lease-to-own plan.

Easiest way is to WhatsApp me at +65 9879 2479. Tell me your room size and whether you already have an air purifier. I’ll tell you honestly what will work for your home.

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