I just acquired a Hot Spring Vanguard VV 2005 Serial Number VV2G1993 from my cousin. Upon hooking it up at our house, we noticed that the main control board, not the heater board, is burnt. I'm looking to replace the control board (p/n 77087) but wondering how the board was burnt in the first place? Could it be a bad sensor or pump? I don't want to buy the $400 board, and burn it up again.
Also, should I be replacing the heater board too?