Customer states there is a musty smell in the kitchen that she believes is coming from the air conditioner. Level 2 duct cleaning performed last year. Technician checked the evaporator coil, the blower, and the drains. System looks very clean. Checked for any air leaks in the ducting. Poured some customer supplied bleach down the drain to ensure it was clear. Being that the smell is isolated to only one or two rooms I want to make sure there isn't a possible plumbing issue. Plumber is scheduled to come out tomorrow to check for any water leaks or a cause of the problem. A germicidal UV system could help with the odor and also help sterilize the air. Estimate has been sent to the customer via email.