Arrived on site to perform fall tune up on a 2016 Lennox system. Furnace and evaporator coil located in attic. Client stated no issues just wanted service. Cycled system in heating. Found filter really dirty due to the area house is surrounded by. Recommend replacing with a Merv16 filter Found new flex ducting and black flex ducting used. Blower assembly and wheel are good just slightly dusty. Motor is good and amp drawls are good and in range. Inducer motor is good and amp drawls. Evaporator coil good. Heat exchanger is good at this time. Blew drain lines out. Slight dirt accumulating in drain lines from dirt that has entered system. All safety switches are operational. Temperature rise is in range and heating. Found system receiving 122.3 voltage. No protection on either unit. Would recommend adding surge protectors on high efficient systems to protect from high voltage that can damage or short out components or damage systems. Cycled system to ensure system operating. Went over summ