Pool Amateur

I just noticed that I'm getting a "Water Sensor Shorted" on the RS8...that's new...

OK, quick Jandy Aqualink Question... I have an RS8 control pad in the house, and a Spa Side 4 button remote. Over the past month, the spa air blower has been turning on by itself, I had a feeling that the 4 button remote on the spa was responsible (becuase it was cracked), so I replaced it and wired in to the power center correctly (I checked this thoroughly). However, over the past few days, the entire system becomes intermittently unresponsive, the spa and heater will turn on on their own, the waterfall will turn on whenever I hit the heater button, I can't move into service mode at the main power center to turn things off, things are just acting crazy... However, if I go to the power center and disconnect the main board from power (by disconnecting the orange and green wire plug) and leave it off for a time (say 2 hours) and then reconnect the main board, everything work fine for a while...but they eventually fritz out again... My pool guys says I need a new main board at the power center ($1,800!!!!!!) but I'm skeptical, I'm thinking it's a faulty relay, and not the main board... Any thoughts out there? Should I try replacing all the relays before springing for a new board? Any other troubleshooting tips?