The McDonnell & Miller 67-G is a float-operated mechanical low water cut-off engineered specifically for steam boilers and millivolt service applications

or noticeable system-wide vibrations

Optimized Response Time: Integrates large air capacity ports that facilitate rapid pilot-to-output conversion

reducing the need for additional fittings during field wiring

Carrier HK06MB012 Pressure Switch 322056-301 The McDonnell & Miller 67-GThe Carrier HK06MB012 is a critical dual pressure switch engineered for induction draft furnace systems. Operating with a precise 0. 68 pressure setting, this OEM HVAC replacement part monitors the pressure generated by the inducer motor to ensure the venting system is clear and operational. It functions as a primary safety limit, preventing the ignition sequence if flue gas path obstruction or inducer failure is detected. This specific model is the