Installed 4 ton Carrier R-410A condenser. Placed condenser on new leveled pad. Installed air handler in upflow position with heat kit. Built and installed new wooden platform the the air handler to sit on. Installed new supply plenum box and attached existing flex duct. Sealed all connections and gaps with mastic. Rebuilt primary drain line, cleared and tested operation. Pressure tested system with nitrogen and pulled vacuum. Installed Honeywell T6 thermostat. Tested heating and cooling operation. Everything is working at completion of service.