Summer months are hot and humid, making an air conditioner a necessity for many households. Unfortunately, the air conditioners smell bad when turned on, creating an uncomfortable environment. To keep your air conditioner running smoothly, it’s crucial to identify the causes of these unpleasant odors.

Throughout this article, we will cover the five most common reasons for a foul odor coming from your air conditioner.

1-Dysfunctioning of Electrical Components
The odor of burning electrical components may indicate that your air conditioner’s electrical components are malfunctioning. A professional needs to address this serious issue immediately so that the system is not further damaged or a potential fire hazard is not created.

2-Problem of Dirty Air Filters
Dirty air filters can cause unpleasant odors. Clogged air filters are caused by dust, dirt, and other particles trapped inside. You may notice that the air conditioner smells bad when turned on or is stale in this case. A three-month air filter replacement is recommended to prevent this.

3-Leakage of Cracked Ducts
A damp air conditioner may also release unpleasant odors. Air conditioning systems can leak if they are not installed correctly or if the ducts are leaky. It is recommended to contact a professional if you suspect moisture in your air conditioner.

4-Producing Chemical Odors
Air conditioners may emit a chemical odor if they have a refrigerant problem. Refrigerants can emit fumes that are unpleasant in odor. A professional should detect leaks and repair them if a refrigerant problem is suspected.

5-Propagation of Mold Growth
Mold growth can also cause unpleasant odors from air conditioners. Air conditioning systems can develop condensation if they are not properly maintained. This can create a moist environment that is ideal for mold growth. It is recommended to contact a professional for mold removal if you suspect mold growth in your air conditioner.


An air conditioner inspection and repair are recommended if you suspect a problem. Crump A/C and Heating System provides you with the best help with air conditioners for any type of problem.

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