I arrived at our clients home for concerns of water dripping from the secondary drain line. I proceeded into the attic and found the large AirHandler with condensation on the exterior of the unit. I checked the drain line and it had a little resistance but not a full clog. Chris informed me that he had a plumber out to clear the washer machine drain, where I believe the primary drain lines for the air handlers are plumbed into. I proceeded to call Trane tech support and they walked me through adjusting the airspeed of the unit. After adding the return air we had not reduced the blower motor speed and it was pulling moisture off of the coil into the cabinet insulation. This was causing the condensation on the exterior of the unit. I took pictures and videos and showed the homeowner what I initially found and what I had adjusted to stop the water issue. We also discussed continuing his maintenance and he elected to renew his maintenance for another year. The system is cooling properl