Resideo 140-240F AquaStat Relay w/ Vent Damper Connection

Product Overview: Immersion-type controllers that combine high limit protection with switching relay control of burner and circulator motors. Features: High limit opens burner circuit only. Select models include transformer and accessory terminals for adding a remote low limit controller. Vertical Mounting Case. Requires a 24 Vac thermostat with heat anticipator set at 0.2A.