Comfort Systems USA Inc provides comprehensive mechanical contracting services, including heating, ventilation, & air conditioning, or HVAC; plumbing; piping & controls; construction; and other electrical components. Projects are mainly for commercial, industrial, & institutional buildings, & tend to be geared toward HVAC. Revenue is roughly split between installation services for newly constructed facilities & maintenance services for existing buildings. The company installs & repairs products and systems throughout the United States. It operates in two segments, Mechanical services & Electrical services, the majority is from the Mechanical services segment.