Field Serviceable: Simplifies repairs by allowing for cartridge replacement rather than full valve removal

and igniters

ensuring reliable performance for 2 PSI and 5 PSI piping systems

it may fit other manufacturers using 1/2" NPT-style thread patterns

Efficient Response: The 1/2" bimetal disc provides rapid contact separation during over-temperature events

Williams P200400 Selector Switch Field Serviceable: Simplifies repairs byThe Williams P200400 F145 30F Selector Switch is a critical temperature actuated control engineered specifically for Williams Forsaire Direct Vent Wall Furnaces and high performance HVAC systems. This OEM Williams P200400 component functions as a dual point thermal safety and operational interface, maintaining precise system thresholds at 145F and 30F. Built with a robust toggle mechanism, it serves as a protective switch to safeguard heat exchangers