McDonnell & Miller 143100 63M Float Low Water Cut-Off

The McDonnell & Miller 63M (143100) is a mechanical low water cut-off for steam and hot water boilers. Its float-operated switch responds to a falling boiler water level to interrupt the burner control circuit.

• Maximum boiler pressure: 50 psi
• For steam and hot water boiler applications
• Use with a TC-4 Test-N-Check valve arrangement on hot water systems
• Manual reset configuration
• No. 2 low water cut-off switch