Xylem-McDonnell & Miller 551-S-HD 551-S Feeder Head Mechanism 136600

The Xylem-McDonnell & Miller 551-S-HD 551-S Head Mech 136600 is a head mechanism intended for McDonnell & Miller 551-S water level controls. To maintain appropriate water levels and guarantee safe and effective operation, these controls are frequently used in steam generators and boilers.  Several internal parts, including switches, levers, and floats, are housed within the head mechanism itself and collectively they monitor variations in the water level. To avoid boiler damage or overheating, the mechanism initiates an automatic shut-off when the water level drops below a safe limit. On the other hand, if the water level gets too high, a feed pump or alarm may sound to bring the level down to normal.