Finally, a reliable temperature controller that does it all. Fully programmable for any temperature between 32F and 90F. High and low temperature audible alarms for added security. Built-in temperature LED display shows F or C. Model TC-200 operates chillers up to 1/2 HP OR heaters up to 1200 watts. Model HC-100 operates BOTH a 1/2 HP chiller and up to a 1200 watt heater with built in safety to prevent both units from running at the same time.