Weil McLain 510-312-152 Control

The Weil McLain 510-312-152 Tankless Heater Low Limit Control is a critical safety and operational component designed for CGT model boilers. As a veteran-grade aquastat controller, this unit features a fixed 8-degree differential and includes the necessary immersion well for direct sensing. Its primary function is to maintain minimum boiler water temperature, ensuring the tankless heater can meet domestic hot water demands without dropping below operational thresholds. This OEM Weil McLain part is essential for preventing the boiler from cycling too low during standby periods, which protects against thermal shock and ensures immediate heat transfer availability. Built for precision in hydronic heating systems, it replaces the Honeywell L4080D1044 and is commonly used in EG water boilers equipped with tankless coils. The robust mechanical bellows and SPST switch configuration provide reliable low limit control, preventing the burner from cutting out prematurely during a hot water call, thereby maintaining system pressure and temperature stability in demanding residential or commercial applications.

• Precise Temperature Regulation: Features a factory-calibrated 8°F differential to ensure stable domestic hot water production.
• Complete Assembly: Includes the immersion well (drywell) for easy installation and accurate thermal coupling.
• Broad Compatibility: Drop-in replacement for Weil McLain CGT boilers and cross-compatible with Honeywell L4080D1044 controls.
• Enhanced System Reliability: Operates as a dedicated boiler low limit to prevent cooling below optimal setpoints, protecting the heat exchanger.

Is the immersion well included with the 510-312-152?
Yes, this specific part number is supplied as a complete kit including the temperature sensing well for direct mounting into the boiler section.

What is the purpose of the 8-degree differential?
The 8-degree differential prevents the burner from rapid-cycling. It ensures that once the low limit is reached, the water temperature must rise by 8 degrees before the burner shuts off, optimizing efficiency.

Can I use this for high-limit protection?
No, the 510-312-152 is strictly designed as a low limit controller to maintain minimum temperatures for the tankless heater. High-limit safety requires a separate aquastat set to interrupt the circuit at maximum operating temperatures.

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.