Have you ever walked into your home and noticed an unpleasant, lingering odor? It can be frustrating, especially when you can't seem to pinpoint the source. Often, the cause of the odor is your air conditioning system. 

This article discusses the most common causes of odor issues in your AC and how to troubleshoot them.

Leaking Oil

Leaking oil from your air conditioner can lead to several problems, one of the most noticeable being a distinct and unpleasant odor. The leak tends to occur from the compressor oil or the lubricant used in the fan motors. When this oil begins to leak, it can produce a smell similar to that of motor oil, which can permeate your home when the AC is running.

Repairing an oil leak in an AC unit can be a complex task, typically requiring professional assistance. However, if you are familiar with HVAC systems, you can attempt to locate the source of the leak yourself. 

Check the oil seals and gaskets in the compressor, as these are the most common sites for leaks. If you also notice any pooling oil around the outdoor unit or any unusual noise coming from it, these could be signs of a leak in the compressor.

If the compressor isn't the source of the leak, the issue may reside in the fan motors. Inspect the motor seals and housing for any signs of leakage. If you discover a leak, replacing the faulty motor may be necessary. 

Chemical Buildup

Chemical buildup is another common culprit behind disagreeable odors emanating from your AC. Over time, airborne chemicals and particles from cleaning products, tobacco smoke, or even cooking can accumulate on the coils and air filters in your AC.

When the AC runs, these chemical deposits can generate a pungent smell, particularly if the buildup involves reactive substances that can degrade or react under heat and airflow.

To identify if chemical buildup is the cause of the odor, you can inspect the evaporator coils and air filters for signs of residue or discoloration. Removing and smelling the air filter can also provide clues — a strong smell usually indicates chemical buildup. 

If you encounter chemical buildup, thoroughly cleaning the affected parts is necessary. This typically involves using a specialized coil cleaning solution to remove the residue, followed by a thorough rinse with water. In case of severe buildup, you might need to replace the air filters completely. 

 For more info about residential air conditioning repair, contact a local company.