Arrived at the customers home to perform an AC maintenance. Upon arrival I put the system into cooling mode and began by checking static pressure. I found static pressure to be failing at this time. I replaced the furnace filter and verified all dampers were fully open and static passed. I gathered CFM counts for the system. I got a temperature split between return and supply air which was 19 degrees. I checked all electrical components which were within manufactures specifications. I examined the blower wheel and found it to be extremely dirty. I moved to the outdoor unit and checked all electrical and refrigerant levels which were within manufactures specifications. I found the outdoor coil to be extremely dirty. I brought issues and options to fix to the customer and he declined repairs today. I washed off the outdoor coil of all film and debris. Customer renewed his membership today as well. System was running when I left.