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How to Eliminate Air Conditioner Odors

While summer is a fun time to enjoy the sun and barbecues, a musty or smelly air conditioner in your home can put a damper on the season. If your AC unit has developed a harsh stench, it's important to get to the root of the problem. Here are the steps you should take to have your home smelling as good as new.

What you'll need:

  • Fin comb - This helpful tool will help straighten bent coil fins.
  • Bleach and water solution - One part bleach and three parts water can clean any mold or mildew with ease.
  • Foaming coil cleaner - This will help clean conditioner coils thoroughly.
  • New AC 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. Make sure the power is 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.