Air Conditioning Filters

25 November 2012

Air conditioner is an essential thing to have in Singapore.  Maintenance of these air-conditioning equipment will involve regular cleaning of the air filters;  also,  the coils may  require chemical cleaning to restore the cooling efficiency from time to time.  This article will introduce a micro non-woven fabric material that will help to keep the cooling coils as clean as possible and to reduce maintenance requirement.

What is Micro non-Woven Fabric Material?

Non woven fabrics are sheet bonded together by entangling polyethylene(PE) or polyester fibers. They are porous sheets that are made from plastic film and not by weaving or knitting. Polyethylene or polyester is used everywhere;  in plastic bags,  plastic films etc.  Non woven fabric has many applications;  one of which is used in mops and brooms that we used to clean the floors. It has natural static charges making it suitable for air filtering work.

Their refills are cheap and a plenty in the market. The refills will cost only around SGD$ 1/= for 35 sheets of 200 x 300. There are 2 types in the market; the other one measured only 200 x 290 can be used for smaller air conditioners.

Application

The fiber sheet is placed just before the original air filter. To stick the sheet to the filter, just use the hook of the Velcro Fabric Fasteners stapled or glued onto the original filter. The hook will “catch” the fiber sheet and secure it in place.

The author has used the non woven fabric material for more than 4 years now without any ill effect on the occupants as well as the air conditioners.

This filter shown below was renewed about one month ago. Dust can be seen accumulating at the corners. When the fiber sheet is lifted up, one can see that there is no dust on the original filter at all except along the sides that was not fully covered by the filter.

Air Resistances

One of the concerns is that the additional sheet of filter will impede air flow. The author has no measuring equipment to measure such impedance. But the fiber sheet was so thin that one can even read the words “e-ion Air Purifying System” clearly written on the original filter as shown in the photo. The air conditioner can still work at its lowest speed without any degrading in performance.

Even if there is air resistance, it won’t be as high as when the fins of the air conditioner were clogged up with dirt; then only chemical cleaning work will restore the efficiency. By then, one would have wasted quite some energy without proper cooling for some period.

Application

This air conditioner shown below has been working every night for the past 4 years.  Non-woven fiber sheet was used since day one. The fins at the coil still looks very clean.  One can even see the reflected shine on the tube of the coil when a touch light was shined at it to take this picture. So far, no cleaning has ever been done on coil.   The gap of the fins is about 1mm which is slightly thinner than a 5 cts Singapore coin as shown.