OEM Lennox Gas Valve — 17H21

The genuine OEM Lennox 17H21 gas valve controls the flow of natural or LP gas to your furnace burners, working with the ignition control to deliver precise, safe fuel metering on every heating call. As a factory-engineered component, it is calibrated to your Lennox furnace's exact pressure and firing-rate specifications, ensuring proper combustion and rated efficiency.

A failing gas valve is a common cause of no-heat and intermittent heating problems. Typical symptoms include a furnace that ignites the pilot or hot surface igniter but never lights the main burners, delayed ignition, short cycling, a clicking valve that fails to open, or a complete loss of heat. Because the valve directly governs fuel delivery, any malfunction should be addressed promptly for both comfort and safety.

Choosing an OEM Lennox 17H21 matters because gas valves are safety-critical devices matched to the furnace's control board, gas type, and manifold pressure. Aftermarket substitutes may not match the required orifice sizing or electrical characteristics, risking improper combustion. This direct factory replacement guarantees correct fit, listed safety compliance, and dependable operation for your Lennox equipment. In stock and ships same day before 3PM CST.