the furnace will drop the flame signal or lockout entirely

Check for carbon buildup on the rod or cracks in the porcelain insulator

028" diameter 395390-28

Is this gasket compatible with other Nor West or Honeywell valve series

Conbraco 20-151-00 Valve Els PW 17895 the furnace will drop theThe Conbraco 20 151 00 is an industrial grade rough bronze water gauge set designed for critical liquid level verification in boiler and hydronic systems. This 1 2" NPT water gauge features a 5 8" OD x 12" length standard glass tube, providing clear visibility of fluid levels under demanding conditions. Engineered for safety and durability, it is equipped with automatic ball checks in both the upper and lower valves to minimize fluid loss and protect