Lochinvar & A.O. Smith 100171557 Gas Valve

The Lochinvar & A.O. Smith 100171557 Gas Valve is an OEM 24V gas control valve engineered for precision fuel regulation in residential and commercial heating systems. Designed for natural gas applications, this 1/2" NPT gas valve features a factory-set 4" WC manifold pressure, ensuring optimal combustion efficiency and burner performance. It is a direct functional equivalent to the Lochinvar VAL1170, providing a seamless drop-in solution for technicians servicing power-vented and atmospheric units such as the Lochinvar DV52 and DV7 series.

Built for the rigors of high-cycle operation, this Smart Gas Valve integrates an internal solenoid and regulator to manage gas flow with high reliability. Contractors often specify the 100171557 gas valve for A.O. Smith water heater repair and Lochinvar boiler maintenance because it maintains strict pressure tolerances across varying inlet conditions. When diagnosing ignition failures or erratic flame signals, verifying the 24-volt signal to this Honeywell or Robertshaw-pattern valve is a standard troubleshooting step. Replacing a faulty control with this genuine replacement gas valve restores system safety and ensures compliance with original manufacturer specifications.

Key Benefits:

• Direct OEM Compatibility: Verified as an identical replacement for VAL1170, eliminating the need for manifold modifications during installation.
• Stable Pressure Regulation: The integrated regulator is calibrated for 4" WC Nat. gas, preventing over-firing and protecting the burner assembly.
• Standardized Connections: Features a 1/2" gas inlet and outlet for compatibility with standard black iron or CSI piping.
• Voltage Efficiency: Operates on a standard 24VAC control circuit, making it compatible with most modern HVAC transformers and ignition modules.
• Reliable Solenoid Operation: Heavy-duty internal coils provide crisp opening and closing, reducing the risk of delayed ignition or gas leakage.

Common Questions:

Is the 100171557 interchangeable with the VAL1170?
Yes, the 100171557 is the current manufacturer part number and is identical in form, fit, and function to the Lochinvar VAL1170.

Can this valve be used for Propane (LP) systems?
No, this specific model is calibrated for natural gas (4" WC). For LP applications, a dedicated liquid propane valve or a manufacturer-approved conversion kit must be used to ensure safe manifold pressure.

What are the symptoms of a failing gas control valve?
Common indicators include the pilot or burner failing to ignite despite a 24V signal, the main burner flickering, or the unit shutting down shortly after ignition due to improper manifold pressure.

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.