Issue FINALLY RESOLVED! Replaced the heater today and that seems to have been one of my many culprits. Hot tub is now heating up. So I assume whatever zapped the battery on my board also took out the heater in the process. After installing that battery…cleaning out the ozone line clog…and replacing the heater- I finally have a functional hot tub. Thank you CanadianSpaTech and everyone else for your help !