I replaced the heater element in my spa and when it still wouldn't heat (but would run), I replaced the electronic control board. The board I replaced was a 6600-287 rev C. The new board is a 6600-720A rev A. After I installed the new board it spa won't fire up at all. I am getting power to the board and past the fuse. The GFCI at the breaker box is not tripping. So I thought the new board was bad, and put the old one back in, since the pumps would run with that board. Same result. The unit will not turn on at all. Any help you can provide would be helpful. Thank You.
