Odoriferous Coil

• A problem called odoriferous coil causes your central air conditioner to smell. Odoriferous coil occurs when a bad smell permeates your unit's condenser coil and the area immediately around it. When your air conditioner runs, the bad smell is blown into your home along with cool air.
  
  

Causes

• Odoriferous coil can be caused when mold and mildew grow on the condenser coil or in the drainage pan nearby. This leads to an unpleasant, earthy smell in your house. Strong odors inside your home can also trigger odoriferous coil. Tobacco smoke can permeate the coil so that the smell of smoke blows back into your home.
  
  

Solutions

• Cleaning the condenser coil will eliminate odoriferous coil. If the problem is caused by mold and mildew, improving drainage in the air conditioning unit will stop the fungus from returning. If an odor inside the home is causing the problem, regularly cleaning the condenser coil will prevent the smell from blowing back into your house.