Air Conditioner Stinks When I turn It On; 3 Shocking Reasons Why Your AC Smells!

You might not know what may be the reason behind “why air conditioner stinks when I turn it on?”, so you start to wonder, what may be the possible reasons? The purpose of an air conditioning system is to provide you with fresh and clean air that lowers the temperatures, especially when you are surrounded by heat.

And it happens inside the unit. A fan takes in the air from your room to the evaporator coils, where the refrigerant takes out the heat, creating cold and refreshing atmosphere. With that, it’ll make your temperature lower by several numbers and will eliminate the heat that you’re feeling.

why air conditioner stinks when I turn it on

The more your air conditioning unit works, the more it’ll need force to accomplish things, and with that, it’ll suck up lots of dust particles and maybe even a problem. To help you find the solutions for that problem, we will learn it in this article. So, keep on reading.


Reasons To Why Your Air Conditioner Stinks When You Turn It On

The air conditioner stinks when I turn it on. There are many reasons why air conditioners can get stinky especially if it isn’t cleaned when you turn them on; it may result from dirt build-up or mildew growth. If you still have your AC’s manual, then good for you; if not, you can at least follow the instructions here so that you can have an idea of its internal parts.

Not everyone knows about this. Air conditioners do not draw air from the outside; instead, they remove it from the heat inside and convert it to cool air. The air is produced called recycled air; the fans inside your air conditioning unit draw air inside the systems and disperses them, resulting in that.

And because of that, dust particles get sucked in and pass through a filter where they gather up. You are resulting indirt build-up, which may be one of the reasons why your air conditioner will smell musty. If you haven’t cleaned yet, start doing it now.

Once you’re finished with this, we can assure you that there will be no problems that you’ll have to deal with anymore, thus giving you the rest that you deserve after a long tiring day of working and doing some errands. Here are the reasons why air conditioners have dirt stuck inside the systems; it will affect the performance and smell of your unit, so make sure to check it often.


Reason #1.Moldbuild-ups on the evaporator coils & fins

Dirt, dust, and moisture can build on the interior evaporator coil after lengthy periods of inactivity, creating an ideal habitat for molds to inhabit and develop. And because of that, the odor will start to smell foul, creating a lousy scent when your air conditioning unit is turned on. So, air passes over the indoor coils for the first time since it has been unused for a long time, air will pick up the decaying odor and carry it around the area.

Causing it to spread and may even carry various germs and illnesses that might affect you and your family’s health. To prevent having that odor, you must first disassemble your air conditioning unit so that you can remove the fin with ease.

Then you’ll want to make a mixture of water and tiny drops of mild detergent; that’ll be the solution that we will use for cleaning the evaporator fins. Clean all the areas where dirt has built up using a soft brush making sure that all of them are removed before you proceed to let them dry. Clean the springs too. After that, put all the parts back, and you can use your AC again.


Reason #2. Mildew growth on the air filters

Mildew development is encouraged by dust, hair, and moisture on the AC’s filter, resulting in a musty stench whenever the air conditioner is turned on. One of the common reasons air conditioning units smell when first turned on, especially if you don’t use forced-air heating in winter seasons.

Among the others, they are the most straightforward problem to deal with as you will only need to clean or replace its filters with a new one. Try purchasing one at your nearest hardware store if an air filter is available that is the same as yours. If not, you can try to buy one online.


Reason #3. Algae and molds present in the drain pan

As they remove extra indoor humidity, air conditioners produce condensate wherein molds and algae grow in a drain pan due to the moisture. They are among the common reasons why overflow happens, causing your air conditioning unit to malfunction; simultaneously, they produce a foul odor.

The first thing that might pop up in your head when you first hear algae is disgusting, right? Well, in a way, it is, but for the sake of your AC, you need to. Now to prevent this from happening, first, make sure that the unit is turned off. Then empty the drain pan and ready a mix of water and bleach for cleaning. Use this to wash the springs and the drain pan to get rid of the smell, and you’re all good.



And that is the answer to your question, “why air conditioner stinks when I turn it on?” Again, there are several methods for every reason that you can use; some apply for many situations, some for only a certain sense. If you cannot handle it yourself, consider calling an HVAC professional to do the job for you.

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