Abstract: A system for applying .[.one-part thermal-cure.]. .Iadd.fluent .Iaddend.material, such as structural epoxy, includes apparatus for heating or cooling the epoxy to a temperature above or below ambient. A spirally coiled tube is suspended within a hollow enclosure by tube end fittings extending from axially opposed ends of the tube. An electrical heater and temperature sensor extend from opposed enclosure ends into the tube coils approximately centrally of the enclosure. The enclosure is filled with a heat transfer fluid that surrounds the coiled tubing. The fluid is connected through an inlet and outlet in the enclosure endwalls for circulation externally of the enclosure through a fluid chiller. A microprocessor-base controller receives input signals from the temperature sensor and a temperature adjustment mechanism, and provides outputs to the heater chiller and heater-exchange fluid pump and circulation valve, and to alarm mechanisms for indicating a high-temperature or low-temperature alarm condition.