Performed AC maintenance on a Lennox XC25. Systems cooling temperature split is 22 degrees. Filter is dirty for being 6 months old. Indoor electrical amp draws are in range. Condensate lines are clear. Duct runs are sealed. Outdoor unit was heavily caked in dirt. This was washed today. Outdoor and indoor units are electrically protected. Compressor and fan amps are in range at this time. Refrigerant levels are ok. System was running at end of appointment.