Tri-City Mechanical is trying its best to keep its cool in the desert. The mechanical contractor, which is a unit of Comfort Systems USA, installs and maintains HVAC (heating, ventilation, and air-conditioning), plumbing, and process systems for new construction and retrofit projects for commercial and residential customers. Tri-City Mechanical's client base is primarily in Phoenix, Tucson, and the surrounding areas. Founded in 1977, the company also forms partnerships with other construction firms and fabricates piping, and plumbing equipment. Tri-City's diverse offerings have allowed it to design and install complete heating, cooling, and plumbing systems for prisons, hospitals, and schools.