replacing 9120 board with 9120BU

[danwood]

have a nordyne heat only old board 9120c1020  no place for the brown wire that was on C goes to gas valve? also have three wires on S123 but only two places

[Admin]

You would need to provide more information.  What is the model o the furnace you're working on? 

[danwood]

Miller/Nordyne G3RA072C-13