McDonnell & Miller PSE801M-120 Boiler Low Water Cut-Off

The Boiler Low Water Cut-Off, specifically the McDonnell & Miller PSE801M-120, protects steam and hot-water boilers with precise probe-based sensing and electronic actuation. Designed for general purpose boiler protection, this unit delivers reliable low-water detection and a straightforward manual reset for safety and serviceability.

UL (Canada and US) and ASME CSD-1 compliant, it features a 7000 Ohm probe for accurate sensing and a compact enclosure suited for standard installations. The device operates at 120 VAC (50/60 Hz, 125 VA) and handles steam up to 15 psi and water up to 160 psi. Temperature ratings span -40 to 120 F for storage, 32 to 120 F ambient, and up to 250 F for water, with humidity tolerance at 85% non-condensing. Includes a standard probe and a manual reset to simplify testing and post‑shutdown restoration.

• Electronic actuation for precise, responsive low-water protection
• Probe-based low-water cutoff with reliable sensing (7000 Ohm)
• Includes standard probe and manual reset for easy testing and reset
• NEMA 1 enclosure for durable boiler-room installations
• UL (Canada/US) and ASME CSD-1 compliant safety performance