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WHY DOES MY AIR CONDITIONER SMELL?


Whether it’s a musty smell, a vinegar odor

or anything in between, you may be asking asking, “Why does my air conditioner smell?”

There are many potential causes of unpleasant smells coming from an air conditioning system, ranging from something as simple as an old filter to more complex issues.


By exploring some of the most common causes of air conditioner smells, your Peace Heating and Air Service Technician can better narrow down the culprit within your system and propose a solution.


1. The Drain Pan is Full

If the air conditioning system emits a musty odor, either during operation or at all times, the first thing Peace Heating and Air professionals will check is the drain pan.

Drain pans that are full and/or clogged will begin to grow mold over time, which will result in a musty odor. The solution here is as simple as replacing the drip pan itself and/or removing the clog.



2.Dirty Filters

The air filter is another simple thing to check when assessing an AC unit for strange smells. This is another problem that will often result in a musty odor emanating while the AC operates.

Usually, this occurs when two different things have happened: the filter has not been changed in a long time and has accumulated a lot of dust and debris, and the AC system is located in a humid climate that causes moisture to accumulate within the filter.

Fortunately, there is a simple solution. Change the air filter!


3. Dead Animal

Any time there is a call to report a rotten smell (such as the smell of rotten eggs) coming from their home’s air vents, this is bad news!

This type of smell is often a dead animal that has gotten trapped somewhere in the home’s ductwork or ventilation system.

Unfortunately, this can be a complex issue to resolve. Your Peace Heating and Air Service Technician will need to figure out the location of the dead animal within the home and then properly remove it. In some cases, these animals can also cause damage to the rest of the home’s HVAC system that may need to be repaired.

If the rotten egg smell cannot be explained by a dead animal, your HVAC technician will test for gas leaks immediately — as this can also be an odor associated with gas.


4. Excess Moisture in Ducts or Vents

For homes in areas that see hot and humid summers, it’s not uncommon for excess moisture within the home’s ducts and/or vents to cause a musty smell. This smell may be especially noticeable while the air conditioning is running. Usually, this is caused by high moisture levels in the air and water droplets settling within the ductwork. Over time, this moisture can lead to mold growth.

As the air conditioning runs, air is pushed through the ductwork, carrying mold spores out through the home’s vents and into the air.

Adding a dehumidifier to your home will effectively remove excess moisture from the air.


5. Frozen Evaporator Coils


Frozen Evaporator Coil


Usually, this problem will only occur after the airflow is blocked from a filter that has gotten so dirty and caked with debris. This, in turn, can cause water droplets to form on the unit’s evaporator coils and freeze as the AC operates.

The good news is that in most cases, frozen evaporator coils will work again once they are thawed out. However, it will also be important for the air filter to be changed and they need to be replaced often. Otherwise, the problem is likely to occur again.


6. Electrical Issue or Short


If something smells like it’s burning while the air conditioning is in operation, it’s generally best to shut off the AC until service call is made by our professional technicians at Peace Heating and Air. After all, these systems have a lot of electrical components, and a short or other electrical issue can cause overheating and even fire.


7. Leak in the System

Sometimes, the drainage pipe or condensate line that drains water away from the condenser can become clogged or leak. When this happens, it is not uncommon for mold and mildew to accumulate and cause musty odors throughout the home.

If there’s a clog in the condensate line, this will need to be cleared.


If you are experience a STINKY AIR CONDITIONER, give us a call and we will be happy to help you find the culprit! We can be reached at 817-855-7014. We services the DFW Metroplex, and surrounding areas!




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