If your air conditioner is emitting a foul smell while running, it’s important that you get it identified and removed right away. More so if the unit is running in tropical climate, because sultry weather conditions are not exactly favorable circumstances for air-conditioning units to run if they are not used and serviced properly.
For AC users experiencing bad odor emissions from their units, the following can be the causes.
Is your AC too large for your room?
ACs need to fit in perfectly to the room size – not more, not less. For example if your room is not too large, a 1-1.5 ton AC would be big enough to cut back on the humidity levels and cool it down. But if your ACs cooling capacity is larger than what is required, it can make way for a musty smell to come across. This is because larger than required ACs are not able to perform the ‘latent cooling’ function properly (which accounts for 70% of an AC unit’s work), i.e. dehumidifying the air to the right extent, in spite of chilling down the air much quicker. Growth of mold spores and stale smell are normal thereafter.
So if you have a reasonably bigger unit in your home and experiencing a foul smell, it can well be because of its size. Call for a professional to check that. 600 SF/ton-800SF/ton is the standard requirement. For older set-ups 400SF/ton can be needed also. Anything larger than this must not however be installed without consulting a contractor.
Is the water drain clogged?
ACs which run for extended hours are often seen to emit foul smell because of clogged water drainage systems in them. In case of the drain being blocked with dirt and grime particles, the water stays back in the ‘condensate’ tray and with time this starts emitting a foul smell. In a tropical climate it is not unusual for bacteria and/or mold to grow within the condenser coil also, which on running the AC, spreads a rotten smell in the house.
Removing the AC cover and freshening up the tray and the drainage holes can solve this problem.
Is your AC being used properly?
Leading AC manufacturers are of the opinion that foul smell emissions can also occur if your air-conditioning unit is not being used properly. Running the AC on ‘Low’ constantly can be damaging for the indoor air quality for instance. This is because dehumidification will not be carried out to the right levels here also, resulting in mold growths and obnoxious odors thereafter.
As a remedial measure, put your AC on the ‘Fan’ mode for sometime so that any accumulated moisture in the vent system of the unit gets released and/or dried up.
In some cases water seepage into the pipes of a central AC, dirty air filters, engine fluid leakage and rotten dead animals in the system’s duct can also induce it to emit a stink. So if you find that your air conditioner is emitting a foul smell its time perhaps to call for the maintenance team to identify and amend it. Your house will start smelling fresh again.