McDonnell & Miller has introduced the Series 150E Low Water Cut-Off/Pump Controller for commercial and industrial hot water and steam boilers. Featuring adjustable 60-second burner-off time delays, the 150E provides continuous primary or secondary protection against low water conditions and rapid burner cycling. Because of its field adjustable 3/4" and 1-3/16" pump differentials, the new controller keeps operation and operating switch levels constant throughout the system's pressure range, reducing pump cycling. McDonnell & Miller. Circle 4.