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A-1 Mechanical Blog

Why Does My Air Conditioner Smell So Bad?

Air Conditioning

Have you noticed a funky odor in your Lansing or Grand Rapids area home lately? If the unwelcome aroma persists despite your best efforts to banish it through extra cleaning and other measures, the source could be something you never thought to consider – your air conditioner.

When an air conditioner smells bad, it leads to a lingering odor and an issue many in the HVAC business refer to as dirty sock syndrome – named after the distinctive smell it produces within the home. A-1 Mechanical explains the source of this unpleasant problem and what to do to rid your home of the stench.

The Reason Your Air Conditioner Smells Bad

A smelly air conditioner and the resulting dirty sock syndrome often stems from mold and mildew within the cooling unit. Your evaporator coil can easily become a prime location for this unwanted growth and collection. Moisture produced through cooling air – combined with poor air filtration and collecting debris deposited by cycling air – deliver prime conditions for mold and mildew to develop and linger.

Issues That Cause Air Conditioner Odors

As explained, the development of mold and mildew produce the foul odor experienced all the way inside the home. Mold isn’t supposed to grow and thrive in a home’s air conditioner. If your AC smells bad, you need to pay close attention to the areas below. Take action to prevent these problems in your Grand Rapids or Lansing area home, and stop cooling system odors from seeping into your living areas.

Inadequate Filtration

Your air conditioning system removes airborne contaminants from incoming air in order to protect sensitive equipment from damage that results when dust, dirt and other foreign matter builds up within. A secondary benefit of this system protection is cleaner air for your living areas. When contaminants are properly filtered out of the home’s air supply, living areas remain smelling fresh.

The first step in fighting dirty sock syndrome is regular air filter replacement. When homeowners neglect this important task, contaminants build up within the air conditioner, contributing to mold and mildew growth.

Today’s homeowners are increasingly concerned with their indoor air quality and the effects it has on a household’s health and comfort. For this reason, many in the Greater Lansing and Grand Rapids areas choose to utilize advanced air filtration methods such as whole-home media air cleaners and ultraviolet air purifiers to increase their control over indoor airborne contaminants. In the fight against dirty sock syndrome, UV air purifiers are especially helpful. Installed within cooling system ducts, this technology neutralizes mold spores, killing them and preventing regeneration.

Whether you rely on just a furnace filter or use advanced air filtration methods to keep your air conditioning system and your indoor air supply clean, these components are only helpful when they operate correctly. Dirty air filters and improperly installed air filtration devices are unable to do their job, which means mold and mildew continue to thrive unchecked.

Dirty Evaporator Coils

When warm air enters the cooling system from the home, it flows over the air conditioner’s evaporator coils where heat is extracted to lower air temperature. Without effective filtration methods in place, contaminants remain in the air supply and have the opportunity to settle on the evaporator coils during the cooling process. Combined with excess moisture, the dust and dirt left on the system’s coils create a breeding ground for mold and odors. The distinct, musty smell of mold is carried back into your home as cycling air moves over the coils during a cooling cycle.

Evaporator coils need to be cleaned for the elimination of dirt, debris, mold and mildew. Homeowners often turn to their trusted HVAC contractor to perform this essential maintenance service to protect the integrity and function of the system.

Clogged Condensate Drain

The cooling process extracts moisture from the home’s air supply, which means the air conditioner’s evaporator coil is normally exposed. The system’s drip pan and condensate drain lines function to remove this byproduct of cooling to control moisture levels within the evaporator coil cabinet, which deters mold growth.

However, if moisture collects in the drip pan and/or condensate drain line and does not properly exit the home, moisture surrounding the evaporator coils increases and creates the conditions mold needs to grow and remain. When your home’s air conditioning unit smells bad, the drip pan and condensate drain line need to be inspected as clogs can develop and block the removal of moisture from the air conditioner.

Extra Large Air Conditioner

Air conditioners that have a capacity too high for the home contribute to mold and mildew development. Oversized air conditioners complete cooling cycles too quickly; the air temperature is lowered to the setpoint before the system is able to dehumidify it. Moisture remains in the air as it travels throughout the cooling system and the home, which enables mold growth and odors in the home.

If Your Air Conditioner Smells Bad, Call A-1 Mechanical!

If your home’s air conditioner smells bad, odor isn’t the only problem you have. Mold and mildew are likely present, and will continue to be until their ideal environment is eliminated within your cooling equipment. There are other AC smells you should keep an eye out for, too. If your AC smells like rotten eggs, it could be an indication of a dead animal in the system or a natural gas leak. Either way, contact an HVAC company immediately.

A-1 Mechanical’s skilled air conditioner technicians are trained to remedy the indoor air quality and cooling system issues that cause mold and mildew to flourish within your equipment. If your air conditioner smells bad, contact us right away. Whether your home needs air conditioner maintenance, repair, replacement or indoor air quality services, we get the job done quickly to restore health, comfort and a clean scent to your household.

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