DIAGNOSIS Moisture and dust inside the cabinet lead to mold on the evaporator coil and in the water reservoir areas. This causes musty smells and reduces efficiency.
FIX Unplug it. Remove the bucket and filter. Use a Phillips screwdriver to remove the rear cabinet panel. Use a soft brush and a vacuum with a crevice tool to remove dust from the coil fins and fan blade. For mold, mix warm water with a little mild dish soap. Dampen a soft cloth—do not soak it—and wipe the coil fins and plastic interior. Rinse the cloth and wipe again. Let everything air dry completely for 24 hours before reassembling.
IF THAT DIDN'T WORK For stubborn smells, use a coil cleaner spray labeled safe for aluminum evaporator coils. Spray lightly, let sit per instructions, and rinse only if the product requires it. Never use bleach or abrasive cleaners.
HEADS UP Never pour water into the unit or use a pressure washer. Do not bend the delicate aluminum fins on the coil. Ensure the unit is bone dry inside before plugging it back in.