United Maintenance, Inc. is Atlanta's premier mechanical contractor providing commercial and industrial air-conditioning, controls and process piping needs since 1974. 24/7 service by highly trained technicians, installation by experienced mechanics, and system design/build by professional engineers make United Maintenance, Inc. your complete mechanical contractor. From simple duct layouts to custom electronic control systems; from light commercial to your heaviest industrial needs, we have the design, installation, and service experience to be your contractor of choice.