Thornton Service, Inc. (TSI) is a commercial HVAC company that offers comprehensive preventive maintenance and service to commercial, industrial, institutional and biomedical research customers. TSI operates and maintains facilities in the Washington, DC, Maryland and Virginia areas. Thornton Service, Inc. was established in 1981 and began its operations as a Linc Service contractor winning the prestigious Linc Contractor of the Year Award in 1993 and 1994. In the early 1990’s, Thornton Service, Inc. established a separate division focused specifically on maintaining mechanical systems in biomedical research facilities. Both the Biomedical Research Facility Management division and the Commercial HVAC Service division provide technical expertise along with operations, maintenance and repair of commercial and research facilities.