Schneider Electric (Barber Colman) 20-850 Plate Els PW 17895 The R33191A001 is specifically tuned

The R33191A001 is specifically tuned for the sequence of operation designated by the control board

When replacing older or fouled rods

This is a screw-in thermocouple designed specifically for natural gas boilers

Standard wrenches are typically all that is needed to access the diaphragm and poppet assemblies via the tee handle adjustment and bottom plug

Schneider Electric (Barber Colman) 20-850 Plate Els PW 17895 The R33191A001 is specifically tunedThe Schneider Electric (Barber Colman) 20 850 serves as a robust thermostat mounting plate designed for professional grade HVAC control installations. Engineered for versatility, this black mounting adapter allows for the seamless integration of 2x2" devices onto standard 2x4" vertical or horizontal outlet boxes. As a direct crossover, the 20 850 is identical to 10 82, ensuring field compatibility for legacy system maintenance and modern upgrades