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Aircon maintenance tips: how to clean an aircon

Learn how to clean window-type aircon and how to clean split-type aircon, to make sure that the cool air you're breathing is fresh and clean.


aircon maintenance tips

Key steps

  • Access your aircon often to check for signs of mildew. 
  • Turn your aircon off completely before cleaning.
  • Do not use bleach or alcohol to clean your aircon. Instead, use non-flammable antifungal sprays or hydrogen peroxide. 

It’s hot and you’ve already set your aircon to the coldest mode, but the room smells funny or it doesn’t seem to be getting any cooler. Don’t worry – your aircon could just need a little clean. As the best thing you can do for your aircon system is to keep it clean, we've compiled a guide with the essentials on how to clean an aircon system. If you want to learn how to clean split-type aircon or how to clean window-type aircon, you'll also find tips in our step-by-step guide below.

Aircon filter cleaning should be done on a monthly basis and, when not in use for long periods of time, it should be covered by a sheet to protect it from gathering dust and mold.

When to clean an aircon?

There will be signs that your aircon is in need of a good clean, especially if you’ve never cleaned the unit since you bought it. 

Signs of mildew (like an odd moldy smell) will tell you that microbes have built up in your aircon so the air coming out of the unit is no longer clean. Because of condensation, it’s perfectly normal for mildew to develop, which means that you should aim to do aircon filter cleaning once a month if you use your unit on a daily basis.

Dust is also bound to be gathered in the cooling fins and coils of your aircon – and the last thing you want is for dust to be spread over you while you sleep. Cleaning the cooling fins and coils of your aircon is just as important as aircon filter cleaning and should be done seasonally. 

How to clean window-type aircon

If yours is a window-type aircon, then follow these steps: 

  1. Turn your aircon off completely. 
  2. Using a hydrogen peroxide solution, spray it over the external area on the front of the unit. 
  3. While the unit is off, remove the filter and spray the hydrogen peroxide inside. When you remove the filter, make sure to have a tray on the floor as drips could stain the surface.
  4. The best way to clean aircon filters is to thoroughly vacuum, before rinsing under lukewarm water. Always check the guidelines for your model to make sure that you're removing the panel properly.
  5. Leave the filter to dry completely before placing it back on the unit. The sprayed exterior of the aircon should also be left to dry completely overnight.
  6. For cleaning the interior of the aircon seasonally, remove the casing, keeping any screws in a safe place. With a soft bristle brush, comb the aluminum fins and air blow them. Vacuum to remove any excess debris. Spray the coils with an oxygenated cleaner or aircon coil cleaner. After 10 minutes, wipe it all with a damp cloth and leave to dry properly before reassembling. 

How to clean split-type aircon

A split-type aircon has 2 components – the indoor unit and the outdoor unit. Here, we’ll teach you how to clean the indoor unit: 

  1. Turn the unit off.
  2. Always check the instructions for your model.
  3. Lift the exterior lid up and pull the air filters off the grille.
  4. Vacuum all dust from the filters. Use a soft bristle brush for any stubborn grime. 
  5. Alternatively, you can wash the filters using lukewarm water and detergent. 
  6. Leave the aircon filter to dry in the shade. 
  7. Remove the frame that gives access to the fan coil, keeping any screws in a safe place. Spray it with hydrogen peroxide solution and rinse it off with a damp cloth. 
  8. Only reassemble everything once all the parts are dry. 

Now that you know how to clean your aircon, you can rest assured that the air you breathe will be clean and mold-free. 

Originally published