Thanks so much for all the good info! I learned about the F7 being the filtration cycle, and found out how to lower it to 2 :). It can cost a few $ to keep a spa going outside year round, so will watch and see if electric bill drops a bit with less daily filtration hours. Some told me that it also could have been an electrical flicker or spike from the local utitility company. I am going to watch and see if it happens again, because it is functioning normally. I'll post again if anything changes. Thanks again for all the help!!!