HVAC USA in Carlsbad operates as a master distributor of commercial HVAC, refrigeration, and fire-control products from Suite G at 2195 Faraday Avenue, a veteran-owned operation established in 2006 under the Mechtronics Controls LLC umbrella. The company distributes controls, actuators, sensors, and thermostats from Siemens, Johnson Controls, Schneider Electric, and Setra Systems, supplying the same product categories installed by Carlsbad electrical contractors like Wheyland Electric. The Faraday Avenue location serves as one of two distribution points — the other in Everett, Washington — fulfilling orders to contractors, facility managers, and building engineers across the western United States. HVAC USA was among the first HVAC/R distributors to sell direct to end users through online access, eliminating the traditional branch-channel markup and account-establishment barriers that had defined the industry. The product catalog overlaps with the field-installation needs of Carlsbad HVAC service providers like Surfside Heating & Air Conditioning, who source controls and replacement components for residential and light-commercial systems. The Siemens and Johnson Controls valve-actuator inventory covers 2-way and 3-way configurations from 1/2-inch to 6-inch pipe diameters, with spring-return and floating-point control signals rated for 0–10 VDC and 4–20 mA input ranges.