Sterling M-8414 is a single-zone temperature control unit designed to circulate water and maintain it at a precise temperature. It features a digital controller with simultaneous display of set and actual temperatures, automatic purge to vent air before startup. The unit has a built-in pressure switch to ensure it doesn't start without water supply, and a safety thermostat for overheat protection. The M-8414 is well-suited for use with various water sources, including city water, chillers, towers, or wells.