Ajax Low Water Cutoffs

See available parts, models and descriptions.

150S Low Water Cutoff

McDonnell & Miller model number 150S is a combination float-operated low water cut-off and pump controller with maximum differential operation, which prevents nuisance burner shut-down in low pressure applications, for steam boilers with a separate water column. This control features an automatic reset with two 120 volt bi-metal snap switches. One switch is single pole, single throw for pump control. The other is single pole, double throw for low water cut-off and alarm actuation. Its maximum pressure is 150 psi and it has a tapped 1″ FIP connection.

150S-HD Low Water Cutoff Head Mechanism

McDonnell & Miller model number 150S-HD is a head mechanism for model number 150S and 157S controls. Head mechanisms include everything except a float chamber. They allow for quick and easy replacement by removing the bolts on the float chamber and then removing and replacing the new unit, with no need to disrupt piping.

150S-M-HD Low Water Cutoff Head Mechanism

McDonnell & Miller model number 150S-M-HD is a head mechanism for model number 150S-M and 157S-M controls. Head mechanisms include everything except a float chamber. They allow for quick and easy replacement by removing the bolts on the float chamber and then removing and replacing the new unit, with no need to disrupt piping.

157S Low Water Cutoff

McDonnell & Miller model number 157S is a combination float-operated low water cut-off and pump controller for steam boilers with an integral water column. The controller has 1/2″ NPT tappings for gauge glass and tri-cocks. This control features an automatic reset with two 120 volt bi-metal snap switches. One switch is single pole, single throw for pump control. The other is single pole, double throw for low water cut-off and alarm actuation. Its maximum pressure is 150 psi and it has a tapped 1″ FIP connection.

94 Low Water Cutoff

McDonnell & Miller model number 94 is a combination float-operated low water cut-off and pump controller with 1-1/4″ FIP tapped connections for steam boilers with a separate water column. This control features an automatic reset with standard number 5 single pole single throw switches. Its maximum pressure is 250 psi.

194 Low Water Cutoff

McDonnell & Miller model number 194 is a combination float-operated low water cut-off and pump controller for steam boilers with water columns. This control features an automatic reset with standard number 5 single pole single throw switches for low water cut-off and pump control. The controller has 1/2″ NPT tappings for gauge glass and tri-cocks. Its maximum pressure is 250 psi and it has a tapped 1-1/4″ FIP connection.