The York S1-031-03010-000 Control Board is an essential part for operating single-stage furnace systems. This control board, which has thermostat input and relay outputs, runs at 24V and is intended to be used with ignition control systems. It acts as the main center for managing all furnace activities. https://www.partshnc.com/s1-031-03010-000-york-single-stage-control-board