What kind of aircon servicing is recommended during Covid 19? The first thing that comes into mind is disinfection, however, how do you disinfect?

Most aircon in Singapore that are used 8-10 hr daily on average, becomes mold and bacteria infested after roughly 1 year of usage. We have to understand why this happens, the reason is simple.

Our aircon recycles the air in the room, there will be organic stuff in the air, even from our human breath (there are more than 3000 different organic compounds in our exhale). However, these are nano particles, you will need to cycle such particles through the system for a very long period of time before it deposits enough organic compound to attract bacteria and mold to show up and break them down.

Good cross ventilation is vital to aircon health, if you open your doors and windows for air exchange daily as long as aircon is not in use, the organic compound is kept to a minimum. But if you don’t open your windows at all, such compounds accumulate and adds up day after day. Because these are nano particles, it is difficult to remove using air purifiers. During Covid 19 outbreak, experts like Prof John Tambyah (NUS), in an interview with CNA expressed skepticism of efficacy in using air purifier to combat the virus, he encourages opening of windows. COVID-19: Health expert skeptical over use of air purifiers even as demand soars

I have been in this industry for almost 20 years, personally handling and disinfecting more than 10, 000 aircon units in my career. I have observed consistently that air purifier don’t work well to prevent mold in an aircon On the contrary, families that uses air purifiers tends to keep windows shut most of the time, that resulted in aircon that is full of bacteria, I’ve seen very moldy aircon, white mold (penicillium), pink bacteria (serracia marcescens), biofilms, all sorts of nasty stuffs.

Things gets worst when there are usage of perfume, scented oil, scented candles. Compared to our exhales, the old particles released from scented products is gigantic in proportion. Families that cook will have more starch, protein and oil in the air. These stuffs diffuse and gets into the rooms. If your room smells of food after cooking, it means that the organic stuff have found its way in. If your room windows are always shut, how do they escape? After some time, the smell may be less or gone, but it doesn’t mean the rich organic stuff have escaped the room.

It is also my observation that families that uses scented products and or with cooking activities, with little or no cross ventilation, will inevitably have very moldy and bacteria infested aircon.

The mold usually grows on the fan blower, an untrained eye will say it is dust. So they keep the windows shut and when the situation doesn’t improve, they buy an air purifier. When an air purifier doesn’t work, they buy a hospital grade air purifier. When a hospital grade air purifier doesn’t work, they take up an aircon maintenance contract that sabotage their aircon and health, without them knowing.

The mold clog the fan blower blades, restricting airflow. Most general servicing contract servicing method use a vacuum cleaner, attach a brush and start removing the mold by brushing. Now their brush is full of mold and using the same brush it starts working on another aircon, in another family, it is spreading. Contact servicing spreads bacteria, mold and now we have covid 19. Such cleaning method is dangerous. Mold cannot be properly removed by brushing, those not removed becomes loose and subsequently becomes airborne when you turn on the aircon.

Bacteria biofilm is what aircon man calls jelly, because it is slimy and jelly liked. If the technician uses the vacuum brush to remove the biofilm, the brush is now full of biofilm. taking the same brush, he brush on the fan coil or heat exchanger, spreading the bacteria to a much larger area.

Have you wondered why is it that when your aircon was brand new, it was trouble free for almost a year or more? but after the first general servicing, the interval gets shorter and shorter? This is because vacuuming method itself is problematic, it doesn’t disinfect but rather spreads bacteria and mold.

Every time they brush the blower, mold become airborne, every time they brush the heat exchange, bacteria colony spreads. They vacuum the drain pipe to stop the leak, the jelly bacteria is in their vacuum cleaner and hose. Do you think they have the time and resources to disinfect their equipment every time they complete one job?

During Covid 19 pandemic, such companies are reinventing themselves as providing disinfection services. Free disinfecting spray on aircon to kill the virus. Well, if the aircon heat exchanger surfaces are infested with a layer of mold and bacteria, it is not going to work very well, the surface itself is not clean. If you don’t throw away your wet food rubbish in your house, can you spray some disinfectant directly into the bin to disinfect it? Try doing it for 2 days without throwing away your wet food rubbish and your house is going to smell like a rubbish chute.