Indoor unit produces a musty or moldy odor when starting

Safety first: Turn off power before cleaning. Wear gloves and eye protection when using coil cleaners.

Steps to try:

• Clean filters: Wash filters thoroughly with soap and water and let them dry.
• Use coil cleaner: Apply a no-rinse evaporator coil cleaner approved for mini-splits to the coil surface following instructions.
• Disinfect drain pan: If accessible, wipe the pan with a diluted bleach solution (or HVAC-safe disinfectant) to kill mold.
• Run in FAN mode: After cooling, run the unit in FAN-only mode for 30 minutes to dry the coil and reduce odor.

When to call a pro: Severe contamination may require professional deep cleaning or chemical washing of the indoor unit.