White-Rodgers 37C73U-171 Valve

The White-Rodgers 37C73U-171 is a professional-grade Natural Gas Water Heater Valve engineered for standard residential tank-style heaters. Built with a 2.5-inch shank for deep-tank insulation compatibility, this control provides precise thermal regulation between 70°F and 160°F. For technicians performing a replacement water heater thermostat install, this unit serves as a direct upgrade for the 37C73U-274 and various A.O. Smith or Rheem OEM controls. This valve features a 1/2" NPT inlet and a 1/2" inverted flare outlet, ensuring standard fitment for most manifold lines. The internal Energy Cut Off (E.C.O.) safety system is non-cycling, providing a critical high-limit fail-safe. With built-in pilot gas filtration and an automatic shut-off mechanism that engages during pilot failure, this 37C73U-171 gas control maintains consistent 4.0" W.C. manifold pressure for optimized burner performance. Whether you are addressing a water heater pilot light won't stay lit issue or a faulty sensing bulb, this 3/4" NPT mount valve is the industry-standard solution for restoring reliable domestic hot water production.

• Universal Compatibility: Serves as a direct technical replacement for 37C73U-274 and select A.O. Smith water heater gas valves.
• Enhanced Safety: Integrated Energy Cut Off (E.C.O.) high-limit switch and automatic gas shut-off in the event of pilot failure.
• Extended Shank Design: The 2-1/2 inch shank length allows for easy installation on high-efficiency tanks with thicker insulation.
• Precise Regulation: Reliable 70-160°F temperature range with factory-set 4.0" W.C. pressure for stable combustion.
• Contractor Ready: Features a standard 1/4" compression pilot connection and a manifold pressure tap for fast field diagnostics.

How do I know if this valve is compatible with my water heater?
This valve is designed for natural gas units and replaces the White-Rodgers 37C73U-171 or the older 37C73U-274. Verify your tank's shank length requirements; this model features a 2.5-inch extension which is ideal for most modern residential tanks.

What causes the water heater pilot light to fail on this control?
Common issues include a restricted pilot orifice or a weak thermocouple signal. This valve includes an internal pilot filter to prevent debris from clogging the orifice, but ensure the pilot assembly is grounded and free of carbon buildup for reliable operation.

Can this valve be used for Propane (LP) applications?
No, the 37C73U-171 is specifically calibrated for Natural Gas only. Attempting to use this on an LP system will result in dangerous manifold pressures and improper combustion.

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.