A method for controlling the temperature of a device is described. The method includes providing a body having a heating/cooling region to which the device is exposed, heating the device with a heating channel provided in the body with one end exposed to the heating/cooling region and cooling the device with cooling channel provided in the body with one end exposed to the heating/cooling region. The heating and cooling channels are provided in the body such that energy propagating in the heating channel is intermingled with gas propagating in the cooling channel and the heating and cooling sources directly impinge upon the device in the heating region.