An apparatus providing effective control of fluid temperature to achieve
temperature control precision of .+-.0.1.degree. F. at flow rates
exceeding five gallons/minute includes a hot and a cold reservoir of
process fluid maintained at their desired temperatures by a high-accuracy
industrial chiller and an industrial heater, respectively. A control valve
mixes fluid from the reservoirs to produce a precisely controlled stream
of process fluid delivered to the point of usage. Another flow control
valve maintains system flow at a precise value.
