Lochinvar & A.O. Smith 100289450 O-Ring 318172-701 this specific suffix (-204) is

this specific suffix (-204) is calibrated and labeled for vertical mount installation only

Safety Compliance: Ensures the system operates within engineered thermal parameters to prevent heat exchanger failure

This genuine OEM Lennox expansion valve is a precision-engineered thermostatic expansion valve (TXV) specifically designed for R410A refrigerant applications

Since this is a conventional 4-wire device

Lochinvar & A.O. Smith 100289450 O-Ring 318172-701 this specific suffix (-204) isThe 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