DG Service Company - Environmentally Safe Contracting, Refrigeration, Air Conditioning, Heating. Installation, Sales & Service. DG Service Company has been providing commercial HVAC/R services to local, private & public organizations for over 20 years. Our mission is to install and maintain HVAC/R systems according to best practices providing quality workmanship and energy efficient products often partnering with reputable local product suppliers, building contractors and real estate management companies. Our client sectors: building contractors, real estate management companies, retail, food services/restaurant, grocery/convenience stores, educational facilities, health care, recreational, public safety, religious, and central AC/Heating installation services for residential home owners. Environmentally Safe-A Commitment to Quality Workmanship.