Springtime Air Conditioning Maintenance for a residential customer near Tribute. Upon arrival found the upstairs system not cooling. Homeowner stated that a previous company said that there was a leak in the evaporator coil. Checked indoor unit and opened up coil door, found oil residue on coil drain pan. Also found 4 one inch filters stacked in four inch section in filter rack. System only needs one one inch filter, or one 16x25x4. Adding more 1inch filters cuts down the airflow through the system. Checked outdoor unit and found pressures low system is about 3-5lbs low on 410-A. Evaporator coil is under warranty, but labor is not covered. Coil is in stock at Lennox in Lewisville. Also outdoor coil needs to be cleaned. Homeowner wanted to hold off on repair for right now.