Ruud air conditioner produces a musty or moldy smell when the blower starts.

Safety first: Turn off power to the indoor unit. Wear gloves and a mask when cleaning moldy components.

• Step 1 – Replace filter: Install a new, dry air filter of the correct size and MERV rating for your Ruud system.
• Step 2 – Inspect coil and pan: Remove access panel and inspect the evaporator coil and drain pan for slime, mold, or debris.
• Step 3 – Clean coil: Use a non-acid, non-rinse evaporator coil cleaner. Spray per instructions and allow to work; the condensate will rinse it away during operation.
• Step 4 – Disinfect pan and drain: Wipe the pan with a mild bleach solution (if compatible with materials) or an HVAC-approved pan treatment. Install pan tablets to inhibit future growth.
• Step 5 – Improve humidity control: Ensure the system is properly sized and that fan settings (e.g., continuous fan) are not causing re-evaporation of moisture.