A few months back I asked on this forum and had a bunch of questions about why my hot tub kept getting the FLO indicator. I believe we decided that the problem at the time was the the filter door was now allowing water in and causing a problem. I now leave the filter door wide open now and didn't have any problem for months after that until recently there was a power outage in my area and the FLO2 indicator came on. I tried recycling power to the hot tub, it did not make any difference. All the various switches had been replaced while we were trying to debug the previous problem last winter.
The service guy also indicated to me some kind of issue with sundance spas where if there is a power outage while the pump is running, it can get locked up and the only way around it is to reseat a jumper on the motherboard. Sure enough, I did that and the FLO2 indicator turned off and everything started working perfectly normally.
(sigh)
Anyone have any knowledge or experience about this issue and work arounds? I might try to install an external switch if I can figure out which pin on the motherboard jumper is the relevant one. That way if I have another power outage and this comes up again I won't have to unscrew the planel off the hot tub to reseat the motherboard jumper, but just wondering if there is some other explanation.