Taco 220-6 1 Npt Ci Univ Flo Chek

Improves boiler efficiency
Universal thread design provides for compatibility with most forced hot water heaters
Cast iron construction for durability
Automatically opens and closes when your circulator activates and deactivates for simple operation; thumb screw allows manual operation in the event that your system’s main circulator stops running
125 psi maximum operating pressure; 277 degrees Fahrenheit maximum operating temperature