Energy Efficiency: Helps maintain system SEER ratings to reduce monthly utility costs

secure fit during installation

Designed to withstand the thermal expansion and high-pressure environments typical of Lochinvar and A

For optimal performance and to prevent condensate accumulation

Direct OEM Match: Fully replaces the legacy AP13156 model with no modifications required for 9-inch ducting and venting systems

Lochinvar & A.O. Smith 100289450 O-Ring R-407A Energy Efficiency: Helps maintain systemThe Lochinvar & A. O. Smith 100289450 O Ring is a critical sealing component designed for high performance gas valve assemblies and burner systems. As an OEM gas valve gasket replacement, this heavy duty sealing ring is engineered from advanced synthetic rubber to provide a precision fit across various hydronic heating platforms. This specific part number, 100289450, serves as the direct replacement for 100288891, ensuring backward compatibility for