Abstract: A pneumatic temperature control unit having a fluid receptacle containing a fluid capable of expanding or contracting with temperature. The fluid receptacle having a surface capable of movement in response to expansion or contraction of the fluid in the receptacle. A spring positioned to exert a variable force on the receptacle surface. The variable force being calibrated for the corresponding fluid temperature above which the receptacle surface moves a desired amount. A calibrated temperature scale to adjustably set the variable force permits the receptacle surface to move at the desired fluid temperature. An elongated trigger mounted to transmit movement by the receptacle surface to a module having structure for controlling the flow of air between an air inlet port and an air output port.