E21 : No Component A Transducer
- Replace the pressure transducer
- Replace the control board
- Check transducer A connection at J3, (E-20/E-XP1) or J5, (E-30/E-XP2) on motor control board.
- Clean the plug and socket of transducer connection by unplugging and spraying commercially available contact cleaner and reconnecting.
- Reverse A and B transducer connections. If error moves to transducer B (E22), replace the transducer A. If error does not move then replace the motor control board.