Manufacturer York Model # ZF24ON24B2AAA2A Serial # NIM3236950 Completed a preventative maintenance maintenance on a roof top unit. I changed out 4 16x20x2 filters 4 16x25x2 filters. I made sure the drain was clear. Then I performed a amperage readings on both condenser fan motors and both compressor and all are operating properly. I looked over the unit and made sure all electrical connections are tight and secure. System is operating properly and ready for summer!!