Unpleasant musty or moldy smell when the air conditioner starts

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

• Clean filters: Wash filters thoroughly and dry.
• Disinfect coil: Spray an approved evaporator coil disinfectant onto the coil fins and allow it to work per product instructions.
• Clean drain pan: Remove sludge and biofilm from the pan and flush with a mild bleach solution (if compatible with materials).
• Dry-out cycle: After cleaning, run the unit in fan-only mode for 30–60 minutes to dry the coil and reduce future growth.