CSLB license #788983 with C-20 and plumbing classifications backs Jackson & Foster Heating and Air Conditioning on University Avenue in La Mesa, a firm tracing its HVAC lineage to 1931 when predecessor Jackson & Blanc began serving San Diego County. The ISL International Service Leadership North American Contractor of the Year designation places the company among an elite group within a network of over 400 HVAC contractors—a caliber of permit-ready engineering that pairs with the architectural planning at firms like The Permit Pro Consultant on La Mesa residential projects. As a Lennox dealer, the shop installs and services Lennox furnaces, air conditioners, heat pumps, and air handlers, with factory-trained diagnostics on iComfort smart thermostat systems and variable-capacity compressor units. The plumbing division handles water heater installation, sewer line repair, and fixture replacement, a dual-trade capability that streamlines remodel timelines for La Mesa homeowners selling through agents like Gregg Phillipson Real Estate in the La Mesa homes for sale market. Highest-tier projects involve complete HVAC system design with Manual J load calculation, Manual D duct design, and HERS-verified performance testing to meet California Title 24 energy-code compliance.