Why Does My Air Conditioner Stink? 7 Shocking Reasons!

Do you smell something weird in your house, and you find out it is coming from your air conditioner, which is why you reflect on why does my air conditioner stink?

Obviously, you want to discover the source so that you can find ways in eliminating it. For your information, a bad smell inside a house might also be an indication of serious hazards. 

Why does my air conditioner stink

The microbes, fungus, pollen, dander, hair, dirt, and dust that have gathered in your unit are the ones causing health issues. Unfortunately, it will also damage the components leading to breakdown and repairs.

Furthermore, it will cause various kinds of smells to come through your vents. There are many more things that you should know, so just read on!


7 Common Reasons Why Does Your Air Conditioner Stink

In this section, you will know the common culprit behind the weird smell coming from your air conditioner. 

Furthermore, you will know what you can do to get rid of them. 

So, why does my air conditioner stink? Here are the following reasons:


 #1. Dirty socks smell

If the drain pans are clogged and the evaporator coils are dirty, it can cause a stinky feet or dirty socks smell. 

Professional cleaning is the solution to this problem. 


#2. Mold, mildew, and must

Excess moisture or humidity in the air conditioning unit can cause mildew and mold build-up. To prevent this from happening, you must improve the drainage, you must fix all leaks, and you should replace filters frequently. 

Furthermore, you need to schedule your AC unit for its annual tune-ups

Another way to prevent mildew and mold from forming in your unit and your house is to have a dehumidifier for the whole house. 

If you schedule your unit for tune-ups, make sure that it will include an overall cleaning. It should detect any problems with mildew or mold. Not only that, but it should also clean the evaporator coils as well as the drain line.


#3. Cigarette smoke

If someone is smoking in your house, the odor of cigarette smoke may accumulate in the evaporator coils and air filter. 

As a result, the air coming from your air conditioner may smell when you turn it on. In such a case, ensure to change the air filter and schedule for a professional cleaning and tune-up. 

Also, tell the smoker to smoke outdoors. 


#4. Sewage

If you have a dry P-trap in your house, then sewer gasses may go into the house. 

You can try to run water of every sink in your house so that you will fill the P-trap with water. This is done to block the sewage smells. 

But after you checked the dry P-traps and it doesn’t seem to be the one causing the problem, then the vent pipe or the sew line might be ruptured. 

In such a case, you need to call an HVAC technician or professional plumber immediately. 


#5. Sulfur or rotten egg

If you smell rotten eggs at home, it can indicate a leaking gas somewhere. 

Natural gas is odorless, but when manufactured it is added with mercaptan. This chemical is the one giving it the distinctive smell of rotten eggs.

Another sign indicating a leaking gas is the shrubs or grass path that colors have changed into orangish or brown.


#6. Burning smell

You can associate a burning smell with mechanical issues such as overheating of the motor or wiring issues. This problem is severe, so you should turn off the system immediately.

In some cases, the smell can be like gun powder. This is an indication of a short circuit in the fan motor or the circuit board of the air conditioner. If the burning smell continues, get out of your house and call the fire department in your area. 

The melting of some plastic components can also give off a rotten egg odor. You have to turn the power circuits off at your breaker box. 

If it is already safe to enter your house again, call for an HVAC professional to ensure no mechanical or electrical problems in your unit. 


#7. Dirty trash stink

If the critter in the duct system dies, it will be hard to ignore its smell. So you need to detect it sooner. 

The very first thing that you need to do is to turn the AC system off and then open the windows and doors for ventilation. 

Then call for a professional immediately. 


Important Things To Remember

In case you are smelling rotten eggs from your AC vents:

  • Do not operate lighter or matches
  • Open the windows and doors
  • Put out the open flames
  • Do not operate electrical items
  • Leave the building
  • Turn the gas supply off and call the gas company


It’s A Wrap!

After you get answers to your question “Why does my air conditioner stink?” and what to do about it, it would be easy to end this issue. 

Remember that if you just try to cover up the smell using scented candles or aerosol sprays, you are just making the air quality worse. 

You should save yourself and your family from health problems such as breathing difficulties, headaches, trouble sleeping, nausea, irritated skin, and eyes. 

Call a professional now and schedule an inspection.

Leave a Comment