I have 1997 Cal Spa Systems 3001. Control panel shows "SN-3" Code -this indicated temperature sensor problem. I installed a new temperature sensor, but control panel still reads "SN-3". Any suggestions or should I replace circuit board.

Thanks!

one thing I would do is to check the Ohm reading on the 2 sensors (the new temp & existing high limit) to see if they are close. The high limit and temp sensor in standing water should read close to the same. If they do, then it sounds like a bad board.