Arrived at customer's house for system inspection. On arrival customer showed me to airhandler systems. Both systems had bio growth in them. System from '04 has alot of buo growth on the fan as well. Suggesting IAQ on both and Suggesting a pull and clean on the blower from the '04 unit. Next went to condensers. Found the old condenser to be low on freon. Capacitors are of acceptable range. Contactors were sending proper voltage. Told customer and customer approved work. Added 2 lbs of freon and unit now running fine. Pressures and readings are all of acceptable range. Collected payment and signature and left. Customer happy