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McDonnell & Miller General Catalogue Industrial Controls

McDonnell & Miller Series RB-122-E Probe Type Low Water Cut-Off

• For residential and commercial applications
• Electronic operation
• Easy to install and wire
• Red LED indicating low water condition
• Green LED indicating power is on
• Test button
• Automatic reset
• No blow down required
• 20,000 ohms probe sensitivity
• Maximum ambient temperature 120°F (49°C)
• Maximum water temperature 250°F (121°C)
• Maximum water pressure 160 psi (11.2 kg/cm2)

The McDonnel & Miller Series RB-122-E probe type LWCOs provide protection against low water conditions. The RB-122-E is for commercial and industrial applications. These controls are fully CSD-1 compliant. Furthermore they are primarily used as LWCOs on hot water heating boilers. If you need a different model other than those listed, please contact us at

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