York S1 031 03482 000 Control Board 321894 706 It is optional for most It is optional for most standard damper applications but becomes mandatory if the crank arm must rotate through the bottom plane or if you are using specific valve linkages like the Q100 Durable Construction: Features silver contacts and heavy duty terminals to resist pitting and ensure long term mechanical reliability in high cycle applications this is an OEM solid state board configured with factory set timings for immediate installation and operation this board manages the critical ignition sequencing and safety protocols required for consistent burner operation