This Resideo AquaStat Relay with Vent Damper is a high-limit, immersion-type controller designed for use in hydronic heating systems. It operates within a temperature range of 140 to 240 degrees Fahrenheit. The device features a transformer that provides power for low voltage control circuits and an SPDT (Single Pole Double Throw) switch activated by temperature changes in the boiler water. Additionally, it includes a vent damper plug, which can be used to connect an automatic vent damper motor. The relay is designed to shut off the burner circuit in the event that the boiler water temperature exceeds the high limit set point, thereby ensuring safe operation of the heating system.
