Lochinvar & A.O. Smith 100187872 Gas Valve 321042-401 this conversion is the standard

this conversion is the standard path to restoring consistent burner sequencing without hunting for discontinued legacy components

it mounts via a standard 2-5/8 inch thru-bolt pattern

This unit is the recognized direct replacement for EF53CK198 and EF53CK185

which can lead to expensive control board damage

The York S1-9951-0861 #44 Gas Orifice is a high-precision LP gas conversion component engineered specifically for York heating systems

Lochinvar & A.O. Smith 100187872 Gas Valve 321042-401 this conversion is the standardThe Lochinvar & A. O. Smith 100187872 Gas Valve is an OEM Natural Gas Valve Venturi Assembly designed for high efficiency water heating systems. This critical component integrates the gas control valve and the venturi into a single, high performance unit to ensure precise fuel to air ratios for optimal combustion. Engineered for A. O. Smith Cyclone and Lochinvar Armor series equipment, the 100187872 assembly eliminates the need for a traditional