They sent a master plumber (Jeff) to fix a water leak on a pipe that runs down from the air conditioning unit into the concrete flooring. He cleaned out any obstructions in the pipe, flushed with a hose, and recommended a cupful of chlorox once or twice a year poured into the open pvc pipe at the top of the unit. This is the inside unit in a closet in the hallway of the house. He was very professional, very pleasant, courteous and included the discount before I even produced a coupon. I have used this service in the past and have always been extremely satisfied with the work and the caliber of people they send out.