McDonnell & Miller 150S-MD Boiler Low Water Cut-Off/Pump Controller

The McDonnell & Miller 150S-MD Boiler Low Water Cut-Off/Pump Controller is a critical safety and control device for commercial and industrial boilers. This mechanical actuation-based unit combines a low water cutoff with a pump controller to protect boiler operation and prevent equipment damage.

Designed for steam and water systems, it features a 1 inch BSPT port connection, a 50 PSI pressure rating, and flexible power options for 120/240 VAC. The unit handles 7.4 A at 120V or 3.7 A at 240V under full load, with higher locked-rotor currents, and includes an alarm circuit rated at 1 A (120V) or 1/2 A (240V). Suitable for commercial and industrial boiler applications, it is UL, CSA, and FM listed to meet rigorous standards.

• Port connection: 1 inch BSPT
• Actuation: Mechanical
• Electrical ratings: 120V/240V input; 7.4 A at 120V, 3.7 A at 240V (full load); 44.4 A at 120V, 22.2 A (locked rotor)
• Alarm circuit: 1 A at 120V, 1/2 A at 240V
• Media handled: Steam and Water
• Pressure rating: 50 PSI
• Dimensions: 13-1/4 in L x 12-7/16 in H
• Applications: Commercial and Industrial boiler systems
• Certifications: UL, CSA, FM listed
• Input supply rating: 120/240 VAC, 345 VA