Complete 2 heat tune up special inspection cumming. Check and upstairs 11 year old system operating with bio growth on air distribution box. Find weak flame sensor and worn ignition. Find duct work dirty. Find downstairs 21 year old Lennox heating system. System operating with worn ignition, weak flame sensor, worn pressure sensor. System under-fire and not efficiency. Find system dirty return duct system. Find Aprilaire humidifier 700 water tube leaking due to crack tube. Give customer options for repair.