Performed preventative maintenance for Evcon and Lennox system. Replaced air filters for both units. (16x25x1) Checked drain pans and drain lines. Checked evaporator coil’s for buildup. Temp split was at 20. Checked both condensing units for dirty coils and checked all electrical components needed for air conditioning. System is operating normally at this time and is ready for the summer season. Gave customer $10 in chub bucks for getting the preventative maintenance done today.