Professional installation is required to ensure the L190-40 temperature rating aligns with the appliance data plate requirements

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

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

This 24V continuous try ignition module is engineered to manage the pilot and main burner ignition cycles

it ensures deep penetration into the plenum for accurate air temperature sensing

McDonnell & Miller 157S-RLS-MD Control R-410A Professional installation is required toThe 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