I was browsing at Daiso at Plaza Singapura & saw a "Filter for air conditioner". The trouble with Daiso is that many of the products have only Japanese instructions on it. This product has both english & Japanese, so I know what it is & how to use it 
It is a sheet about 80 x 40 cm which you can cut to size & fix it on to your aircon.
It is something like the 3M Filtrete for airconditioners, http://www.amazon.com/Filtrete-Cond...UTF8&qid=1426822974&sr=1-5&keywords=3m+filter
The one in Daiso is only $2 each.
It is a sheet about 80 x 40 cm which you can cut to size & fix it on to your aircon.
It is something like the 3M Filtrete for airconditioners, http://www.amazon.com/Filtrete-Cond...UTF8&qid=1426822974&sr=1-5&keywords=3m+filter
The one in Daiso is only $2 each.
