Air conditioning maintenance. Cleaned and serviced the outdoor condensing unit. Tested all mechanical parts. Found the capacitor completely empty on both sides of the compressor and fan. The system would not turn on at all. The contactor was extremely corroded. Replaced the cap using 45/7.5 and replaced the contactor as well. Cleaned the unit well, the system was extremely loaded with cottonwood. After cleaning, I checked the charge and found the system low on R410 refrigerant. Added 2 lbs of refrigerant and system sealant. Charged system to factor specs and 10.6 ° of subcooling. Customer signed up for maintenance program. Using one visit now and they will have one more visit prepaid for the fall season. Customer does have a Boiler system for heating. Replaced both return air filters that customer provided.System is cooling and operating as it should be now at this time.