How to Eliminate Air Conditioner Odors

Summer is a time full of memorable and nostalgic scents like freshly mown grass and burgers on the grill. You don't want a musty or smelly air conditioner to get in the way of your enjoyment of the season. If your air conditioner has developed a stench, get to the root of the problem yourself by following these steps.

What you'll need:

  • Fin comb. This will straighten bent coil fins.
  • Bleach and water solution. One part bleach and three parts water will help you clean any mold or mildew.
  • Foaming coil cleaner. This will help clean conditioner coils thoroughly.
  • New filter. You may need to replace your filter, so always have one on hand.

Step 1: Cut power to the unit.

As with all repairs, safety is the first priority, so power off and unplug the air conditioner.


Step 2: Change or clean the filter if needed.

Filters should be changed every 30 to 60 days, depending whether you have pets, allergies or a naturally damp home. Clean the filter by removing the mesh filter and front grill of the unit and washing them with the bleach solution to kill odor-causing bacteria.


Step 3: Clean the coils and straighten the fins.

If you spot mold or mildew, clean the evaporator coils behind the filter and condenser coils at the back with coil cleaner. If the coil fins are slightly bent out of alignment, an inexpensive fin comb will straighten them out to improve airflow and prevent future build-up.


Step 4: Check the drain line.

If the drainage system gets clogged with dirt particles, water can build up in the drip tray. In humid climates or when the unit is running constantly, this water may not evaporate and will begin to develop odor-causing bacteria and mold. Clear the drainage holes, flush the drain line with bleach solution, and use this same solution to clean and disinfect the tray.


Step 5: Run the air conditioner on high.

If your unit is running on a low setting for an extended period of time, the air may not be dehumidified enough to prevent mold growth. After you've gone through all the steps to clean it, be sure you're running the unit on high occasionally to prevent mold growth.