A system for and method of precisely controlling the temperature of an electronic component through a range of temperatures by controlling the temperature of a gas forced into contact with the component is disclosed. The system comprises a dual control loop including two sensors, one for measuring the temperature of the gas and the other for sensing the temperature of the component, for controlling the temperature of the gas so as to provide accurate control of the temperature of the component.

 In a system for precisely controlling the temperature of a substantially solid object through a range of temperatures, said system including (a) support means for supporting said object; (b) means, responsive to a control signal, for controlling the temperature of a fluid; (c) means for directing said fluid into direct contact with an object supported by as support means so as to control the temperature of said object; (d) means for generating a first signal as a function of the current temperature of said fluid; (e) means for generating a second signal as a function of the desired temperature of said fluid; and (f) means for generating said control signal as a function of the different between said first and second signals.