An apparatus for cooling a gradient coil assembly of a magnetic resonance
imaging (MRI) system and for controlling a temperature of a magnet warm
bore is provided. The gradient coil assembly includes an inner gradient
coil assembly and an outer gradient coil assembly. A first cooling
circuit is provided that has a cooling tube positioned at a distance from
the inner gradient coil assembly. The cooling tube of the first cooling
circuit is configured to transport a first coolant having a first
temperature. A second cooling circuit is provided that has a cooling tube
positioned at a distance from the outer gradient coil assembly. The
cooling tube of the second cooling circuit is configured to transport a
second coolant having a second temperature. The apparatus also includes a
controller coupled to the first cooling circuit and the second cooling
circuit. The controller is configured to independently control the first
temperature of the first coolant and the second temperature of the second
coolant.