4 Tricks to Remove Bad Odors from Air Conditioners

If you notice that your air conditioner smells bad, it's time to put into practice some tips to eliminate that bad smell. Check them out here!
4 Tricks to Remove Bad Odors from Air Conditioners

Last update: 24 June, 2022

Did you turn on the air conditioner after several months and notice a rather unpleasant smell? This is much more common than you may think, because with the arrival of warmer days, the appliances come to life once again and it’s normal that it emanates a different aroma. Fortunately, there are some tricks to remove bad odors from air conditioners that we’ll take a look at in this article.

Actually, the appliance itself doesn’t produce any odor, but this is caused by factors outside it that affect its parts, such as filters, exchangers, or dirty fans. Also, having the drain in bad condition and the air circulating through the equipment can cause this. Let’s take a look at why this stench is generated and how you can get rid of it.

Why does the air conditioner smell so bad?

Several months have passed since the last time we turned on the air conditioner and, in doing so, this means that it may emanate a smell as particular as it is unpleasant. This is due to the fact that during the period of little use, dirt has accumulated in the different parts that compose it, among other causes.

For example, dust particles can become trapped in the filters, in the fan, and in the drain pan. If we don’t clean them properly at the right time, they become damp, and after a while, fungus forms.

Remember that the appliance absorbs air from the environment, so we must pay attention to the quality of this air. If there’s tobacco smoke, food odor or garbage, they will also go into the air conditioner.

remove bad odors from air conditioners
The different parts of the appliance can accumulate substances or be damaged and thus generate unpleasant aromas.

Now that we know where this smell comes from, let’s see how to put an end to it.

1. Remove bad odors from air conditioners: Clean the filter

Dirty filters are often the main cause of an air conditioner smelling bad. The function of these parts is to filter the air and prevent bacteria and other microorganisms to proliferate and damage the operation of the equipment.

Similarly, dirty filters reduce the efficiency of the device, so it will consume more energy and  won’t work properly. For all these reasons, it’s essential to keep them clean.

To clean them, simply remove them, rinse them with warm water, and rub them gently with your hands. If necessary, you can use neutral soap, but never use abrasive products or hard bristle brushes, as these could damage the composition of the elements. Let them dry before replacing them.

The filters of split units are located on the inside of the unit, at the front. Therefore, you have to lift the cover and you will see them there.

We think you may be interested in reading this, too: How To Reuse the Water From the Air Conditioner

2. Clean the inside of the unit

Cleaning the filters will help to remove the bad smell of air conditioning, however, you must pay attention to all of the parts of the equipment that may be causing the odor. In the case of the interior, you must focus on its ducts. You can use special disinfectants that can be specially purchased for this task.

3. Remove bad odors from air conditioners: Clean the drain

Air conditioners expel water due to condensation. This phenomenon occurs when the humidity is removed from the interior, which is colder than the environment.

This is where the droplets that go into the drain pan come from. The problem arises when water accumulates and is not removed. This can happen if the slope of the hoses isn’t ideal.

Moisture that doesn’t leave can cause problems and a bad odor. In this sense, moisture is perfect for the proliferation of fungi.

To avoid this situation, we must dry the equipment. While it’s true that some modern machines have self-cleaning filters that eliminate viruses and bacteria, there are still many appliances that do not.

In these cases, at the end of the summer season, we can turn on the air in ventilation mode for a few hours. In this way, the moisture that has remained will disappear and with it, the possibility of microorganisms.

Another way to dry the air conditioner is to pass it to heat mode for a few minutes. This will ensure that it dries all the way.

4. Take care of the ambient air

As mentioned above, the equipment works with the air circulating in the environment, so it’s essential to take care of the quality of it. Tobacco, food, garbage and smoke from other facilities are some of the factors that affect the device.

Humo cigarrillo ensucia el aire.
If cigarette smoke is captured by the air conditioning equipment, then there will be bad smell when it runs.

Like this article? You may also like to read: 19 Tips to Protect Yourself from the Effects of Air Pollution

Regular maintenance is the best trick to remove bad odors from air conditioners

We hope you can apply some of these tips and finally put an end to the bad smell emanating from your air conditioner. Anyway, we want to emphasize that the maintenance of this type of equipment should be done on a regular basis.

It’s important to prevent the accumulation of dirt from more than one season, as it will be more difficult to remove later. Finally, when in doubt, you should contact professional installers, because these are delicate machines that require skilled labor.


All cited sources were thoroughly reviewed by our team to ensure their quality, reliability, currency, and validity. The bibliography of this article was considered reliable and of academic or scientific accuracy.


  • Quadri, N. P. (2001). Sistemas de aire acondicionado. TECNIBOOK EDICIONES.
  • Aponte Rodríguez, L. A., & Albarracín Martínez, L. (2016). Diseño, mantenimiento, suministro e instalación de sistemas de aire acondicionado.
  • Poot Poot, E. D. J. (2018). Experiencia laboral en mantenimiento preventivo de aires acondicionados tipo minisplit.
  • Sulaiman, N. A., Abdullah, M. P., Abdullah, H., Zainudin, M. N. S., & Yusop, A. M. (2020). Fault detection for air conditioning system using machine learning. IAES International Journal of Artificial Intelligence, 9(1), 109–116.
  • AGUDELO, A. M. G. DESARROLLO E IMPLEMENTACIÓN DE UNA METODOLOGÍA PARA ORIENTAR A USUARIOS DE SISTEMAS DE AIRE ACONDICIONADO EN LA ELECCIÓN DE LA MEJOR OPCIÓN BASADO EN CRITERIOS ECONÓMICOS Y AMBIENTALES, EN LA EMPRESA AIRE ACONDICIONADO Y VENTILACIÓN SAS.
  • Maldonado Fuertes, M. A. (2013). Comparación de los Sistemas de AC Inverters y Convencional. Civil Engineering;.

This text is provided for informational purposes only and does not replace consultation with a professional. If in doubt, consult your specialist.