SureFit Heating & Air is a C-20 HVAC contractor in Normal Heights, San Diego, holding CSLB #1053734 and operating from Adams Avenue in the 92116 ZIP code. Owner Juan Carlos Segura runs the BBB-accredited firm with permitted project history covering furnace replacements, air conditioning installations, ductwork modifications, and mini-split system installs. The C-20 classification authorizes fabrication, installation, maintenance, and repair of warm-air heating systems, ventilating systems, and air-conditioning units including all associated ductwork, registers, flues, and thermostatic controls. Post-installation cleanup after ductwork modification and mechanical equipment changeout projects goes through The Clean Bear, whose crews clear construction debris and HVAC dust from finished spaces. Normal Heights' housing stock — predominantly 1920s through 1940s bungalows and Craftsman homes — often lacks central HVAC, making ductless mini-split systems the most practical retrofit for heating and cooling without the cost of cutting duct chases into plaster walls and hardwood floors. Furnace replacement on homes with existing duct systems involves matching the new unit's BTU output and airflow capacity to the existing duct sizing, and the firm runs Manual J load calculations to confirm the replacement equipment is correctly rated for the home's square footage and insulation levels. Air conditioning installation covers split-system and packaged-unit configurations, with refrigerant line sets, condensate drain routing, and electrical disconnect wiring included in the scope. Remodeling projects that include HVAC upgrades often align with broader interior redesign timelines, and Abbas Upholstery & Design coordinates upholstery and interior finish work on renovation projects where mechanical system changes affect ceiling heights, soffit dimensions, and wall cavity access. The firm also handles commercial HVAC for retail and restaurant spaces along the Adams Avenue business corridor, where rooftop package units and make-up air systems require different sizing calculations than residential equipment.