Installation of Lennox XC20 variable-speed air conditioning system completed today for residence in Tahoka. The 18 SEER, 3-ton system replaces an inefficient 10-year-old unit that experienced compressor failure. Installation included complete replacement of evaporator coil, TXV valve, and refrigerant lines to ensure compatibility with R-410A refrigerant. Upgraded electrical service to accommodate higher efficiency equipment specifications. Modified supply plenum to improve airflow characteristics and reduce static pressure. Installed Lennox iComfort S30 smart thermostat with humidity control capabilities. System start-up procedure included vacuum testing to 500 microns, proper refrigerant charging using manufacturer's subcooling method, and comprehensive performance testing. All operational parameters well within acceptable ranges. Final inspection confirmed proper condensate drainage, accurate temperature splits, and correct electrical load measurements. Provided customer with detaile