Musty AC Or Heat Pump Odor, Aka Dirty Sock Syndrome

Do you have a musty smell that reminds you of dirty socks? AC or Heat pump odor is sometimes referred to as “dirty-sock” syndrome. The smell is not only obnoxious, it can be unhealthy to breathe especially if you suffer from allergies or asthma.

This is usually caused by mold or mildew growing inside your ducting and or on your system’s evaporator coils. They grow where there is moisture. This dirty sock, musty odor can be eliminated by cleaning the inside of your heat pump system wherever moisture builds up.

Mold requires moisture to grow. Cleaning ducting, evaporator coils and condensate pans is best done using an approved fungicide or mold cleaning solution.

How to remove heat pump odor

  • Turn off your system
  • Inspect for moist areas and also look for standing water. Clean with a cleaning solution designed to kill mold and approved for use in HVAC systems.
  • Replace anything porous that has become moist of wet such as filters or insulation.
  • Clean the coils of your system with the cleaning solution.
  • Clean condensate pans and pumps with the cleaning solution. Stagnant water is a major source of odor.
  • Clean the ducting and registers with the cleaning solution.

Control of mold and mildew should only be done using cleaners approved for use in HVAC systems that are made to control mold and mildew.  You can also use a product such as Air Scrubber Plus that works with your HVAC system to continually kill surface mold and prevent musty heat pump odor.