McDonnell & Miller 157S-R-M Pump Controller 30067439-890 Featuring a DPST (Double-Pole Single-Throw)

Featuring a DPST (Double-Pole Single-Throw) switch mechanism

Corrosion Resistance: The high-grade plastic body construction protects against environmental degradation in diverse mechanical rooms

This "short cycling" is frequently caused by a dirty or failing furnace flame sensor that cannot maintain a consistent signal to the control board

Its durable construction is built to withstand the corrosive environment of high-efficiency 90%+ AFUE furnace systems

This model is commonly utilized as a panel mount pneumatic gauge in control cabinets to monitor various parameters across the HVAC pneumatic loop

McDonnell & Miller 157S-R-M Pump Controller 30067439-890 Featuring a DPST (Double-Pole Single-Throw)The McDonnell & Miller 157S R M (Part Number 177306) is a heavy duty, float operated low water cut off and pump controller designed for commercial and industrial steam boilers. This unit features an integral water column and alternate tappings to simplify installation on various boiler configurations. The 157S R M is functionally identical to the 172817, utilizing a snap acting SPDT switch that eliminates the need for mercury while providing reliable