This is a BRAND NEW Trane/American Standard Control Circuit Board! The Board # is CNT03797 and the White Rodgers part # is 50A55-486. (OEM Replacement for all the Board Part #s Below). Board comes with instructions although installation is intuitive. Thanks for looking and good luck!
The control board is the "brain" of your unit, coordinating and executing the operation of other various components by sending voltage when and where needed. A control board is constantly monitoring sensors and safety switches in the unit.