How to Clean Your Aircon Filter: A Step-by-Step Guide for Singapore Homes
- ✍️ By City Cooling Management
- 🏷 Aircon Maintenance · Aircon Servicing · DIY Care
Cleaning your aircon filter is the one maintenance job most Singapore homeowners can safely do themselves on a wall-mounted unit. City Cooling recommends it between professional services: it takes less than 10 minutes and needs only a sink, a towel and a few basic precautions.
Below: how often to do it, the safe step-by-step method, what the filter light on your unit means, and the signs that cleaning the aircon filter is not enough.
1
How often should you clean your aircon filter in Singapore?
City Cooling recommends cleaning the air filters every two to three weeks if you run your aircon daily. Clean them more often if you have pets, live near a main road or building works, or run the aircon for long hours.
Not sure if it is time? Slide the filter out and look at it. If it is visibly grey, dark or matted with dust, it needs cleaning.
Filter cleaning is not the same as aircon servicing. A service also cleans the coil, flushes the drainage and checks the refrigerant, none of which you can reach yourself. For servicing intervals, see our guide on how often to service your aircon.
2
Before you start: what is safe to do yourself
You can clean the filters and wipe the vents yourself between professional services. Anything involving refrigerant, wiring, the inside of the unit or the aircon ledge should be left to a technician. Follow these rules every time:
- Switch off the aircon and the power at the wall switch or breaker. Turning the unit off with the remote alone leaves it powered.
- Use a stable step stool or ladder. Do not stand on a bed, chair or sofa to reach the unit.
- Never climb onto the aircon ledge or lean out of a window to reach the outdoor unit. Leave anything on the ledge to a technician. Our HDB aircon servicing guide explains the ledge rules.
- Never spray water into the unit. Wipe the vents and front panel with a damp cloth instead.
- Filters only. If something behind the filter looks dirty, damaged or wet, leave it for a technician.
3
How to clean your aircon filter, step by step
To clean an aircon filter, switch off the power, open the front panel, remove the filters, rinse them, let them dry fully and refit them. The steps below are for wall-mounted units, and follow the care advice published by manufacturers such as Samsung and Mitsubishi Electric. The same steps apply whether you call it washing or cleaning your air con filter.
What you need
- A sink or basin
- A clean towel
- A vacuum cleaner with a brush attachment, or a soft brush
- A little mild detergent, only for stubborn dirt
- A stable step stool
Steps
- Switch off the power at the wall switch or breaker.
- Open the front panel. On most wall-mounted units it lifts upwards until it clicks and stays open. Do not force it past its stop.
- Remove the filters. Unclip each filter and slide it out. Note which side each one came from, so you can refit it in the same place.
- Remove loose dust. Vacuum on low power or brush gently with a soft brush.
- Rinse the filters. Run lukewarm water through the back of the filter, the clean side, so the dust is pushed out the way it came in. If the filter is heavily soiled, soak it in lukewarm water with a little mild detergent, then rinse it well. Do not use hot water, bleach or harsh cleaners, and do not scrub the mesh.
- Dry them completely in the shade. Keep the filters out of direct sun, which can warp the frame. Never refit a damp filter: moisture inside the unit leads to smells and mould.
- Refit the filters and close the panel. Each filter should sit flat in its frame with no gap at the edge. If the filter has a FRONT marking, it faces outwards.
- Switch the power back on and reset the filter light if your unit has one (see below).
4
Should you wash or replace your aircon filter?
The standard mesh filter on most wall-mounted aircons is designed to be washed and reused, so it rarely needs replacing. Some units also have add-on filters, such as deodorising or fine-particle filters, which follow different care rules set by the manufacturer. Some fine-particle filters should only be vacuumed, never washed, and some deodorising filters are meant to be replaced rather than cleaned. Check your user manual before you clean anything other than the mesh filter.
Replace a mesh filter only if it is torn, warped or no longer sits flat in its frame. City Cooling can source replacement filters for the brands we service. Send us your brand and model number on WhatsApp to check availability.
5
What does the filter light on your aircon mean?
Many aircons have a filter reminder light or message. It switches on after a set number of running hours to remind you to clean the filter. It is not a fault, and the aircon keeps working. How the reminder appears depends on the model: some units have a dedicated filter light, some Samsung units show "CF" on the display, and some show a message on the remote.
The reset method also varies by model. On many units you hold a filter or reset button on the remote or the indoor unit for a few seconds after cleaning. Check your user manual for the exact steps, or WhatsApp us your brand and model number and we will tell you how.
A blinking light that comes with an error code is different: that is the unit reporting a fault. Our aircon error codes by brand page explains what to do, and we also have dedicated pages for Mitsubishi aircon servicing and Daikin aircon servicing.
6
Common mistakes that damage your aircon filter
Most filter damage comes from rushing the job. Avoid these mistakes:
- Refitting the filter while it is still damp
- Using hot water, bleach or harsh cleaners
- Scrubbing the mesh, which tears it
- Drying the filter in direct sun
- Forcing the front panel past its stop
- Running the aircon with the filters taken out
- Spraying water into the open unit
7
When is cleaning the filter not enough?
A clean filter keeps a healthy aircon working well, but it cannot fix dirt or faults deeper inside the unit. If cleaning the filter does not improve cooling within 30 minutes, the issue lies elsewhere. These signs mean the problem is behind the filter and needs a technician:
- A musty smell comes back soon after cleaning. This usually means mould on the coil or blower, which an aircon chemical overhaul or chemical wash removes.
- Airflow is still weak with a clean filter. The coil may be blocked and need a chemical wash.
- Water drips from the indoor unit. This is usually the drainage, not the filter. See our guide to aircon leaking water.
- The room never gets cold. See aircon not cooling: 8 common causes.
8
Cassette and ducted units: does the method change?
Yes. The steps above are for wall-mounted units. Cassette and ducted units sit in the ceiling, so whether you can reach the filter yourself depends on the unit and on whether there is an access panel in the ceiling. If there is no access panel, or you would need to work from a ladder at ceiling height, leave it to a technician.
For ducted, cassette and VRV systems in offices or larger homes, see commercial aircon servicing.
City Cooling's BCA-certified technicians handle aircon servicing in Singapore for HDB flats, condos, landed homes and offices, 7 days a week. If your filters are clean and the aircon still is not right, book a general service or WhatsApp us on 9890 9677. You can see our rates on the price list.
Frequently Asked Questions (FAQs)
Can I use my aircon without the filter?
Can I wash my aircon filter with soap?
How do I know if my aircon filter is dirty?
Does cleaning the filter replace aircon servicing?
Why does my aircon still smell after I cleaned the filter?
Get StARTED
Need Aircon Servicing Help?
Comment
Ops! No feedback yet!
Be the first to share your experience!
Share Your Experience
Your feedback helps others make informed decisions.
