Weil McLain 511-842-370 Transformer

The Weil McLain 511-842-370 Transformer is a critical OEM replacement part engineered for high-performance voltage regulation in residential and commercial boilers. As a step-down control transformer, this component is designed to convert 120V primary voltage to a stable 24V secondary output, providing the necessary 40VA power rating to drive ignition modules, gas valves, and integrated boiler control systems. This HVAC control transformer is a direct replacement for the Honeywell AT140B1297 and is vital for maintaining the electrical integrity of your heating system's low-voltage circuit.

For field technicians, ensure that the Weil McLain 511-842-370 is utilized specifically within compatible hydronic systems to prevent control board failure. This 40VA 24V boiler transformer features a foot-mount configuration for secure installation within the cabinet. It is rigorously tested for compatibility with Weil McLain boiler models including the AHE, GV (Series 1-4), GV90+, HE II, CGT, CGS, CGi, and CGA series. Reliability in the 24VAC control circuit is paramount for avoiding nuisance lockouts and ensuring consistent sequence of operation.

• Direct OEM Compatibility: Verified for use in Weil McLain GV, CGi, and CGA series boilers, ensuring seamless integration with existing wiring harnesses.
• Optimized Power Delivery: Provides a consistent 40VA power rating, sufficient for driving multiple 24V loads without secondary voltage sag.
• Rugged Foot-Mount Design: Simplifies replacement tasks by matching the standard mounting footprint of factory-installed units.
• Standardized Electrical Specs: Features a 120V primary and 24V secondary configuration to meet the specific demands of modern HVAC control logic.

What boiler models use the Weil McLain 511-842-370?
This transformer is compatible with a wide range of units, including the Weil McLain GV90+, GV Series 1-4, CGi, CGa, and HE II boilers.

Can this transformer replace a 20VA or 30VA unit?
Yes, the 40VA rating provides a higher power capacity, making it a robust upgrade for systems originally equipped with lower VA rated 24V transformers.

Is the 511-842-370 a direct swap for the Honeywell AT140B1297?
Correct. This part serves as the official Weil McLain replacement for the AT140B1297, maintaining identical electrical specifications and mounting points.

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.