Duct Dynasty Heating & Air holds CSLB license #1010169 and operates from Suite 6 at 4401 Twain Avenue in Grantville, a San Diego HVAC contractor less than a quarter mile south of Mission San Diego de Alcala on the Mission Gorge Road corridor. Brian Burnette founded the company in June 2016 after 14 years as a field installer, taking over the same Twain Avenue building where predecessor company Indoor Weather had operated since April 1980 under founder Jack Hoskin. Plumbing tie-ins for hydronic heating loops and condensate drainage on commercial jobs along Mission Gorge Road run through American Plumbing Group, which handles the supply-line connections on combined mechanical projects in the Grantville corridor. That lineage gives the shop more than four decades of institutional knowledge on the HVAC systems installed throughout the 92120 ZIP, including the original builder-grade forced-air units in Grantville's light-industrial flex spaces and the residential systems in surrounding Allied Gardens and Del Cerro. The service menu covers AC repair and installation, furnace diagnostics, heat pump conversions, ductless mini-split systems, ductwork fabrication, smart thermostat installation, whole-home humidifiers, and zone-control damper systems. Every new equipment installation carries a 10-year manufacturer warranty plus a two-year labor guarantee backed by the company. Burnette's crew maintains direct experience with the A2L refrigerant transition, stocking R-454B for new installations alongside R-410A for existing systems, and each technician carries EPA Section 608 Universal certification. Homeowners replacing single-pane windows during an HVAC upgrade often find that the new thermal envelope changes the Manual J load calculation, and the shop factors in window specifications from contractors including Newman Windows and Doors before finalizing equipment tonnage. The family-operated structure includes Burnette's sister and two sons on the crew, maintaining the small-team continuity that Hoskin established in 1980. Duct fabrication runs on a Pittsburgh lock seam machine capable of producing 4-inch to 24-inch round and rectangular trunk lines in galvanized 26-gauge sheet metal on site.