McDonnell & Miller 51 Water Feeder

The McDonnell & Miller 51 (134700) is a heavy-duty mechanical water feeder engineered for low-pressure steam and hot water boilers with a capacity exceeding 5,000 sq. ft. Designed for rigorous commercial and industrial applications, this unit provides precise proportional feed action to maintain optimal water levels without the need for complex electronics. It features a high-capacity float-operated valve and a quick-change replaceable cartridge that includes both the valve and strainer, allowing for streamlined periodic maintenance by field technicians. With a maximum vessel pressure of 35 PSI and 1" NPT connections, the Series 51 ensures reliable make-up water delivery under supply pressures up to 150 PSI. For contractors looking to enhance system safety, the unit can be field-upgraded with a No. 2 switch to integrate a low water cut-off function, ensuring the burner circuit is interrupted if levels drop below safe thresholds.

• Continuous Water Level Regulation: Provides consistent proportional feed to prevent the hazardous dry-firing of large-scale boiler systems.
• Simplified Serviceability: Features a quick-change cartridge valve and strainer, reducing downtime during annual inspections and repairs.
• Flexible System Integration: Rugged 1" NPT connections and a field-upgradeable design allow for the seamless addition of LWCO protection.
• High-Pressure Tolerance: Supports a maximum water supply pressure of 150 PSI and can withstand inlet temperatures up to 120°F.

• Can the Model 51 be used on both steam and hot water systems? Yes, it is rated for both low-pressure steam and hot water boilers, provided the vessel pressure does not exceed 35 PSI.
• How do I add a low water cut-off switch to this feeder? The Model 51 is designed for field upgrades; a No. 2 switch can be installed directly onto the unit to add burner-interruption safety features.
• What maintenance is required for the internal valve? It is recommended to inspect the internal strainer basket and valve cartridge annually. Because it is a modular cartridge design, the entire assembly can be replaced without repiping the unit.

This item is not eligible for free shipping.

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.