21M51U-843 – CONTROL BOARD (2-STAGE, PSC)

Description

The White-Rodgers 21M51U-843 Control Board is a universal, two-stage furnace control designed for systems equipped with Permanent Split Capacitor (PSC) blower motors. This control board replaces various OEM models, including those from Goodman, Amana, Lennox, Trane, and York, ensuring broad compatibility and simplifying inventory management. It features a 120 VAC ignitor output, two-speed inducer output, and supports both single and two-stage gas valves. The board includes a tri-color LED for furnace status indication, selectable blower delays, and a push-button for fault recall, enhancing diagnostic capabilities. Additionally, it offers outputs for humidifier and electronic air cleaner integration, providing comprehensive control over furnace operations.

• Brand: White-Rodgers
• Model: 21M51U-843
• Type: Universal Two-Stage Furnace Control Board
• Compatibility: Replaces various OEM models from Goodman, Amana, Lennox, Trane, and York
• Voltage: 120 VAC ignitor output
• Features:
  • Two-speed inducer output
  • Supports single and two-stage gas valves
  • Tri-color LED for status indication
  • Selectable blower delays
  • Push-button fault recall
  • Outputs for humidifier and electronic air cleaner integration
• Function: Controls furnace operations, including ignition, blower motor, and safety features

Cross Reference and Older Part Numbers
The 21M51U-843 control board replaces the following part numbers:

• Goodman/Amana: 10207708, 10207712, 10207713, 20300001, 20300003, 50A51-215, 50A51-225, 50A51-235, 50M61-288, 50M61-289, PCB00114, PCB00115, PCB00116, PCBBF114, PCBBF114S, PCBBF115, PCBBF115S, PCBBF116, PCBBF116S, PCBBF120S, PCBBF125
• Armstrong: 43207001, 44957001, 50A51-210, 50A51-211, R43207001, R44957001
• Johnstone: L39-373, L39-376, L42-300, L42-301, L42-302
• Trane/American Standard: 1006225, 1148167, 21M51-495, 50A51-405, CNT03077, CNT6424, D344301P01, KIT15943, X13650839010
• York/JCI: 18381, 18384, 449573, 50A51-242, PCBBF112, PCBBF112S, PCBBF113, PCBBF113S, S1-33103010000, S1-33103010001, S1-33103010002, S1-33103010003, S1-33103010004, S1-33103010005, S1-33103010006, S1-33103010007, S1-33103010008, S1-33103010009, S1-33103010010, S1-33103010011, S1-33103010012, S1-33103010013, S1-33103010014, S1-33103010015, S1-33103010016, S1-33103010017, S1-33103010018, S1-33103010019, S1-33103010020, S1-33103010021, S1-33103010022, S1-33103010023, S1-33103010024, S1-33103010025, S1-33103010026, S1-33103010027, S1-33103010028, S1-33103010029, S1-33103010030, S1-33103010031, S1-33103010032, S1-33103010033, S1-33103010034, S1-33103010035, S1-33103010036, S1-33103010037, S1-33103010038, S1-33103010039, S1-33103010040, S1-33103010041, S1-33103010042, S1-33103010043, S1-33103010044, S1-33103010045, S1-33103010046, S1-33103010047, S1-33103010048, S1-33103010049, S1-33103010050