When should the S1-2805-4711 harness be replaced during a service call

Durability: Features aluminized steel construction to resist oxidation and scale buildup during high-fire cycles

cross-reference the serial number of your unit with the manufacturer's parts list before installation

What is the difference between K16BT-18 and K16BT-18H

Williams P625471 Control Board 319848-301 When should the S1-2805-4711 harnessThe Williams P625471 Control Board is a critical genuine OEM replacement part designed for precision furnace orchestration in high efficiency Williams heating systems. As a direct fit gas valve control module, this board manages the ignition sequence, flame sensing, and blower timing to ensure safe and consistent heat cycles. For technicians troubleshooting intermittent failures or lockout codes, installing this HVAC circuit board eliminates the