Why Does My AC Smell?

There is no worse feeling than turning your AC unit on during a hot spell – just to be welcomed by an awful stench filling your home. After a few years of usage, your AC unit can begin to develop a smell, indicating something needs to be fixed or cleaned.  

There are many different scents that your unit can be expelling, each with a different cause and solution associated. Once you understand what each scent is telling you, a professional from Ball Heating & Air Conditioning can help you eliminate it. 

AC Repair Smells

Mold or Must 

This is the most common smell that can come from your AC unit. Typically, this means that water has accumulated in the drip lines or drain pipe, leading to fungus, mold or mildew growing in your unit. Having your system thoroughly cleaned will remove the smell – but if there is a leak in your system, it should be repaired to prevent further problems.  

Another reason could be a filter needing to be changed. If you live in a hot and humid climate, moisture can accumulate on dirty filters, leading to a musty smell. This can be easily prevented by changing your filters every 1-2 months.  

Car Exhaust 

Although your AC unit does not run on fuel like a car engine, there are some points when it can smell as if it might. If your unit is smelling like your car, the refrigerant line within your system might be broken or cut. A leak in your refrigerant line can release hazardous chemicals into your home’s air. Call a professional to repair the broken line ASAP, and turn the unit off to prevent any circulation of the chemicals in your home’s air.  

Smoke or Something Burning 

There are many different electrical components within your system that make it function, including circuit boards, wiring, fans and more. If a burning or smokey smell is coming out of your AC unit, any one or multiple electrical components in your system could be broken and, in fact, burning.  

Another reason for the burning smell is a collection of dust buildup. If the unit hasn’t been used for a long period of time and is sitting stagnant, dust can pile up and result in a burning odor when the unit is turned back on. This smell is only temporary and is nothing to be too concerned about.  

Rotten Eggs or Sulfur  

Any foul smell coming means that a small pest or critter most likely died within your AC system. Sometimes animals take refuge in your system’s ductwork and get trapped, which eventually leads to their death. This, in turn, builds up a rotten smell over time. Have a professional locate where the smell is the most pungent so they can open up your ductwork and remove the animal.  

A Skunk or Rotten Cabbage 

This is an indication of a gas leak – something that is very dangerous if not addressed immediately. Natural gas does not have an odor, but methyl mercaptan does have a skunk-like smell to it. If this smell is present, turn the gas supply to your AC off immediately and call a professional to fix it ASAP. This gas is toxic and a tell-tale sign of something seriously wrong in your system.  

Cigarette Smoke 

If you smoke inside, the AC unit will eventually smell like evaporated cigarette smoke as it gets filtered through your system. A way to beat this is to change the filters in your system and clean out your AC system regularly. Additionally, smoking outside will eliminate any future problems indoors.  

Professional AC Odor Repair 

For the majority of your smelly AC problems, try to not repair the AC smell on your own. A professional can ensure that any issue in your system is solved safely and efficiently without any chance for potential harm.  

For more information on keeping your AC odorless in the future, contact Ball Heating and AC for clean and pristine air.