Approaches presented herein enable cooling a data center with a cooling system having a relatively high coolant temperature. This cooling system is controlled by a building management system and includes piping through which coolant flows, an air cooling unit in thermal contact with the coolant, and a chiller to cool the coolant to a temperature between 18 and 22 degrees Celsius as instructed by the building management system. The building management system uses a chiller controller to vary the chilling of coolant within a range of 18-22 degrees Celsius, thereby controlling the air temperature within the data center to within a required temperature range. Because the building management system maintains the coolant temperature to 18-22 degrees Celsius, the cooling system can be simplified by excluding typical cooling system components such as variable flow control valves and their controllers. This simplification decreases the need for maintenance and reduces operating cost.