The Series PSE-800 probe type LWCO uses patented technology to monitor changes in water conductivity. When defined parameters are exceeded the new PSE-800 makes a decision to shut the burner off based on the volatility/variability of the resistance readings. This new patented technology provides the best protection possible without turning off the boiler unless a low water condition exists. As an added measure of safety, the control will turn off the boiler if it recognizes an out-of-water...

Mcdonnell & Miller (153828) PSE-801-U-120 Steam Boiler Low Water Cutoff 120volt with Extended Probe. The Series PSE-800 probe type LWCO uses patented technology to monitor changes in water conductivity. When defined parameters are exceeded the new PSE-800 makes a decision to shut the burner off based on the volatility/variability of the resistance readings. This new patented technology provides the best protection possible without turning off the boiler unless a low water condition...