McDonnell & Miller 751-P-MT-120 Boiler Low Water Cut-Off

The McDonnell & Miller 751-P-MT-120 Boiler Low Water Cut-Off is a dependable safety device designed to protect boilers in commercial and industrial settings. This probe-type low water cut-off uses electronic actuation for precise, reliable operation in demanding boiler rooms.

Designed for steam and hot water systems, this unit features a 3/4 inch threaded port for straightforward installation and a compact footprint compatible with retrofit projects. Its UL-listed rating (US and Canada) and NEMA 1 enclosure provide rugged protection in typical boiler room environments. The unit operates from 24 VAC and consumes minimal control power, making it easy to integrate with existing control circuits. The included standard probe and a 20k Ohm sensing element ensure responsive shut-off when water level falls.

• Probe-type low water cut-off with electronic actuation
• 3/4 inch threaded port for simple installation
• 24 VAC input with low power consumption
• UL-listed for US and Canada; NEMA 1 enclosure
• Suitable for steam and hot water applications in commercial/industrial boilers
• Standard probe included; 20k Ohm probe sensitivity
• Wide operating range: ambient 32–120°F; storage -40 to 120°F