The Balboa 54378-03 Circuit Board is a great replacement for the discontinued Great Lakes and Four Winds PCBs for the GVS500SZ system. This circuit board works with both VS501S and VS501SZ systems and provides reliable operation, easy installation, and simple troubleshooting.

Tech Tips:
When ordering a circuit board, you must use the chip number to identify it accurately. This chip number can be found on the white sticker near the center of the board. It is important not to rely solely on looks as different boards can have very similar appearances but vastly different functions and components. To ensure the accurate identification, use the chip numbers and any other identifying numbers printed on the board to confirm the correct board.

Fitment guidelines:
Used in VS501S and VS501SZ Control Boxes

Additional Information:
Replaces 389275, 53268, 54377, 9710-115, FVS501SZR1A, KEYS100, MVS504SZ, VS501SZRD2, 54378-01, 54378-02, VS501R1B, and 55197 GVS500SZ