McDonnell Miller, Series 157S Low Water Cut-Off/Pump Controllers ( 173502 )
Installation Manual
Replacement Parts
Specification Sheet
Features and Benefits
- For residential, commercial and industrial low or high
- pressure boiler applications
- For boilers of any steaming capacity
- Monel bellows provides corrosion resistance
- Float chamber with integral water column provided
- Snap action for high temperature service
- 1 Single pole, single throw switch for pump control
- 1 Single pole, double throw switch for low water
- cut-off and alarm actuation
- Optional features
- Manual reset
- Integral conductance probes for additional levels and
- greater operating differential-Model 157S-RBP-MD
- 1" or 114" NPT equalizing tappings
- 12" or 34" NPT tappings for gauge glass/tri-cock
- installations
- BSPT threads
- Maximum pressure 150 psi (10.5 kg/cm2)
- For new electronic 150E Series see page 37
- Model 157S-MD
- Maximum differential operation
- Prevents nuisance burner shutdowns in low pressure
- applications
- Maximum operating pressure 50 psi (3.5 kg/
