The procedure for replacing a SPD board is as follows:
1) Remove the screws on the front panel of the board and remove the faulty SPD board.
2) Push the new board into the SPD slot and make sure that the board is in position.
3) Tighten all the screws on the panel with a #2 cross screwdriver.
4) Check if the the SPD is operating normally.
When the SPD is operating normally, the SPD ALARM will be shown on the LCD screen.