McDonnell & Miller 150E Series - User Manual

Series 150E and 157E
Low Water Cut-Off/Pump Controllers
For Steam Boilers and Other Level Control Applications
Typical Applications:
– Primary or secondary pump controller/
low water fuel cut-off
for steam boilers
– Motorized valve controller
– Low water and high water cut-off
– Dual pump control
– Alarm actuator
A
B
• Before using this product read and understand instructions.
• Save these instructions for future reference.
• All work must be performed by qualified personnel trained in the proper application, instal-
lation, and maintenance of plumbing, steam, and electrical equipment and/or systems in
accordance with all applicable codes and ordinances.
• To prevent serious burns, the boiler must be cooled to 80˚F (27˚C) and the pressure must be
0 psi (0 bar) before servicing.
• To prevent electrical shock, turn off the electrical power before making electrical connections.
• This low water cut-off must be installed in series with all other limit and operating controls
installed on the boiler. After installation, check for proper operation of all of the limit and
operating controls, before leaving the site.
• To prevent serious personal injury from steam blow down, connect a drain pipe to the control
opening to avoid exposure to steam discharge.
• To prevent a fire, do not use this low water cut-off to switch currents over 16A, 1 Hp at
120 VAC or 8A, 1 Hp at 240 VAC, unless a starter or relay is used in conjunction with it.
Failure to follow this warning could cause property damage, personal injury or death.
W
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WARNING
Series 150E
Series 157E
®
with
MERCURY
FREE
1 HP
Relays
Installation & Maintenance
Instructions MM-414

McDonnell & Miller 150E Series Specifications

General

Brand	McDonnell & Miller
Model	150E Series
Category	Controller
Language	English

Summary

Series 150 E;157 E Product Overview and Safety

Typical Applications

Lists common uses like pump control, valve control, and dual pump applications.

Critical Safety Warnings

Highlights essential safety instructions before operating or servicing the unit.

Specifications and Features

Electrical Ratings and Switch Data

Details voltage, current, and horsepower ratings for various applications.

Key Operational Features

Covers features like burner time delay, redundant cut-off, and pump off functions.

Switch Settings and Flange Configuration

Flange Position Settings

Explains how to adjust switch settings based on flange position for optimal operation.

Installation Procedure

Determining Installation Elevation

Guides on selecting the proper height for the low water cut-off controller.

Mounting and Piping

Step-by-step instructions for physically installing the device onto the boiler system.

Water Gauge Glass Installation

Details the process of fitting the water gauge glass for level monitoring.

Remote Mounting of Control Box

Control Box Mounting Guidelines

Provides instructions for locating and mounting the control box away from the main unit.

Probe and Control Box Wiring

Explains the wiring sequence for connecting probes to the control box terminals.

Electrical Wiring and Diagrams

Circuit Board Layout

Identifies components and terminals on the main circuit board for wiring.

Wiring Diagrams for Applications

Illustrates different wiring configurations for various boiler control scenarios.

Testing and Operation Adjustments

Indicator Lights and Testing

Explains the meaning of indicator lights and how to perform functional tests.

Burner Delay (DOB) Adjustment

Details how to set the time delay for burner shut-off after low water is detected.

Troubleshooting Common Issues

Problem Diagnosis and Solutions

Provides guidance on identifying and resolving common operational problems.

Maintenance and Blow Down

Scheduled Maintenance

Outlines routine maintenance requirements for the control unit.

Blow Down Procedure

Describes the correct method for performing a blow down of the control.