I preformed a maintenance on a 2016 Lennox unit. Outdoor unit: I checked amps on the compressor and fan motor, I checked the capacitor, I checked the vacuumed the drain lines and the bottom of the unit, I checked around the contactors and the board, I washed the unit down with water. Indoor unit: I checked amps on the blower motor, I checked the capacitor, I checked the coils, I checked the drain pans and drain lines, I checked the electrical wires and connections, I checked the float switch, I cleaned the filter grills. The only thing I recommend is a ss2 float switch for the drain line for the indoor unit.