Conducted cooling maintenance on Lennox XC25 variable-speed condensing unit matched with SL280V variable-blower air handler. Verified proper refrigerant charge on R-410A system by checking superheat/subcooling. Cleaned condenser coils. Inspected electrical components and tested operation across full range of modulating capacity. Cleaned/checked drain line and replaced air filters. Cycled through all modes ensuring within Lennox's rated parameters.