Lochinvar & A.O. Smith 100172017 Gas Valve

When you're out in the field facing a combustion failure on a Lochinvar boiler or A.O. Smith water heater, the 100172017 Gas Valve is the exact OEM drop-in you need to restore reliable ignition. This 24v gas valve is engineered specifically for liquid propane (LP) systems, providing a fixed 10" wc (water column) manifold pressure to ensure the burner remains stable under high-demand cycles. It features a robust 3/4" NPT inlet and outlet, providing the flow capacity required for high-BTU residential and light commercial heat exchangers.

Mechanically, the 100172017 is identical to the VAL3404, making it a critical stock item for vans servicing models like the Lochinvar Knight and Copper-Fin series. This replacement gas valve utilizes a high-torque solenoid actuator that responds instantly to the 24V signal from the integrated control board, eliminating the lag often found in generic alternatives. For technicians performing HVAC troubleshooting, this valve's design simplifies manifold pressure testing via dedicated taps, ensuring the fuel-to-air ratio is dialed in for peak efficiency and reduced carbon buildup.

• Direct OEM Match: Fully replaces 100172017 and VAL3404 with no piping modifications required.
• LP Specific Calibration: Pre-set for 10 inch WC to maintain consistent liquid propane combustion.
• High Compatibility: Fits an extensive range of Lochinvar and A.O. Smith models, including the 985, 2070, and 1255 series.
• Industry Standard Connections: Features 3/4" NPT threading for a secure, leak-proof seal during gas valve replacement.

• Can this valve be used for Natural Gas? No, this is a dedicated LP gas valve set for 10" wc. For NG applications, a different regulator spring or valve assembly is required.
• How do I verify the solenoid is active? Ensure you have a constant 24v signal at the terminals during the ignition sequence; if voltage is present but the valve doesn't open, the internal actuator has likely failed.
• Is the VAL3404 really the same part? Yes, the 100172017 and VAL3404 are cross-referenced as identical components by the manufacturer.

Disclaimer: While we strive for 100% accuracy, product data and specifications are subject to change. Please contact our team to confirm compatibility or technical details before purchasing.