Why does my air conditioner smell bad?

At Pujol Clima we receive this question almost daily and there are times when we cannot explain why an air conditioner smells so bad, especially when the room we use does not have bad odors or smoking, but the truth is that we can begin to notice a certain strange smell that appears when we turn on the air conditioner.

Is my air conditioning unit smelly?

It should be made clear that the air conditioning machine, by itself, does not produce odors, what happens is that the machine generally sucks in the air that, if it carries some type of unwanted particles and they lodge in our system, can accumulate and produce some type of odor, when turning on the unit, it will move and distribute it throughout the area, giving the sensation that it is our air conditioning machine that smells bad.

To make everything much clearer, we will list the possible causes of bad odors in different sections.

Dirty Filters

A common cause of unpleasant odors is dirty filters. We often forget that air conditioning equipment requires preventative maintenance at least once a year, and cleaning the filters is extremely important for proper operation.

What happens if I skip cleaning?

When we neglect this cleaning, the filters become clogged and saturated, preventing them from functioning properly and causing that dirt to pass into the indoor unit, thus filling it with grime. This dirt, combined with the moisture produced in the heat exchanger and the indoor fan when operating in cooling mode, will cause a multitude of bacteria and fungi to proliferate in these areas, resulting in the typical musty smell so characteristic of poorly maintained air conditioning units.

This is the most important step in keeping our air conditioner odor-free. Once dirt has passed through the filter and settled on the internal heat exchanger, the drain pan, and the vent, cleaning will become much more difficult and expensive.

There is not enough slope on the indoor unit drain

The indoor unit's drain can also produce odors. All air conditioning units have a drain because they all condense moisture when producing cold, and this generates water. This water must be expelled somewhere, and this is what the indoor unit's drain does, channeling this water somewhere.

How can a drain produce a bad smell?

When the indoor unit's drainpipe doesn't have a sufficient slope for proper drainage, water will accumulate in the tray of our indoor unit, which can degrade and generate unpleasant odors.

The use of air fresheners

Never use air fresheners of any kind when you have the air conditioner on, because these odors, which initially smell wonderful as they repeatedly pass through the filters and the interior of the unit, will create an unbearable smell every time the unit starts to ventilate. This happens because the particles stick to the different components, creating a terrible odor over time.

I've kept my air conditioning equipment up to date with maintenance, but it still smells bad. Could air fresheners be the reason?

Yes, if your air conditioner is always clean, with regular maintenance and other maintenance, but the bad smell still persists, make sure you're not using air fresheners such as wall-plugs, incense, sprays, or any other type of air fresheners.

These odors are very difficult to eliminate once they appear because the air must pass through the entire internal circuit of the unit to cool or heat it, leaving everything impregnated with these substances. So, if you use air fresheners, I recommend that you avoid using them at least when the air conditioner is running.

Find the bad smell and work to eliminate it.

Knowing all this, we just need to figure out why our air conditioner smells bad and where it's coming from so we can fix it.

There are many miracle sprays that promise to get rid of bad air conditioning odors, but the reality is that if we don't find the source of the smell and the problem at hand, it's hard to solve. So, if your air conditioning smells bad, get to work and find the source of the bad smell.

The most important thing is to have it properly maintained by a specialized company. At Pujol Clima, you'll find your partner for preventive maintenance on all your equipment. We've prepared a package tailored to your needs. We also offer a free improvement study for the air conditioning in your home or business.