this control simplifies field service by maintaining the original footprint and electrical terminal configurations

and York packaged units

Precise Control Logic: The 50 square inch diaphragm delivers higher torque and positioning power compared to smaller size 150 units

Simplified Field Service: Standardized terminal markings allow for faster installation and testing during maintenance calls

this model is specifically tested to meet UL555S standards

McDonnell & Miller 157S-RLS-MD Control R-410A this control simplifies field serviceThe McDonnell & Miller 157S RLS MD (Part Number 177251) is a high performance mechanical combination low water cut off and pump controller designed for commercial and industrial steam boilers. Engineered for high pressure applications up to 150 psi, this unit features a maximum differential operation that effectively prevents nuisance burner shutdowns in systems experiencing rapid water level fluctuations. Its integral water column design simplifies