Most OEM fan blades utilize a integrated hub with a pre-installed set screw for securing to 1/2" shafts

The McDonnell & Miller 176319 Electrode is a high-pressure probe designed specifically for industrial hydronic and low-pressure steam systems

Installing it on a lower voltage will result in insufficient wattage

Common signs include the blower motor running constantly

Surface Mount

Utica-Dunkirk 550002583 Control Module R-410A Most OEM fan blades utilizeThe Utica Dunkirk 550002583 Control Module is the designated OEM boiler control replacement for high efficiency hydronic systems. This unit is the primary integrated furnace control board, engineered to orchestrate the ignition sequence, blower timing, and safety circuit monitoring for Utica and Dunkirk condensing gas boilers. As the direct successor to the legacy 550002298, it ensures seamless HVAC system diagnostics and maintains strict operational