Weil McLain 511-330-186 Pilot Assembly

The Weil-McLain 511-330-186 Natural Gas Pilot Assembly is a critical OEM replacement component designed for constant-burning, thermally supervised standing pilot systems. Engineered for high-temperature durability, this assembly ensures consistent ignition and flame rectification across several flagship boiler lines. It is a drop-in HVAC replacement part for Weil-McLain CG, EG, EGH, LGB, MGB, and PFG series boilers. This assembly includes the pilot burner, natural gas orifice, and bracket configuration necessary to maintain a stable flame, preventing the nuisance lockouts and ignition failure common with aged or carbon-fouled components.

For contractors servicing older hydronic systems, the 511-330-186 pilot assembly provides the precise millivolt output required for reliable gas valve actuation. When performing a boiler maintenance cycle, replacing the entire burner-fixed assembly rather than just the thermocouple often resolves intermittent pilot light outages and ensures the sensing lead is correctly positioned within the flame envelope. This genuine Weil-McLain part is built to factory specifications to handle the thermal stress of continuous operation without warping or premature signal degradation.

Key Benefits:

• OEM Compatibility: Precision engineered specifically for Weil-McLain CG boilers, EG, and MGB series, ensuring exact fitment and alignment.
• Thermally Supervised Safety: Features a robust design that maintains steady ignition to prevent unburned gas accumulation.
• Natural Gas Optimized: Factory-set with the correct pilot orifice for residential and commercial natural gas configurations.
• System Reliability: Eliminates downtime caused by soot buildup or oxidized ports on original burner heads.

Common Questions:

What boiler models use the 511-330-186?
This assembly is primarily used in Weil-McLain CG, EG, EGH, LGB, MGB, and PFG series gas-fired boilers.

Does this include the thermocouple or pilot tubing?
It includes the standing pilot burner and bracket; however, it is standard practice to inspect or replace the associated 30-inch screw-in thermocouple and pilot tubing during installation to ensure system integrity.

Can this be used for Propane (LP) conversions?
No, this specific part number is calibrated for Natural Gas. Using it with Propane requires a different orifice size to ensure proper combustion and safety.

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.