I went away on a weeks vacation just as this happened so I threw a good dose of shock into the tub and turne3d off the main breaker to the tub.
When I came back, just for kicks, I turned the breaker back on and got no "FLO" error !
When I left for work in the morning I went ahead and cranked up the heat setting to 99 and when I gto home, still no "FLO" error and the tub was up to 99 degrees.
I could not detect any bubbles at all coming out of the return jet so I stuck my hand in there and could feel the water being pumped out good and strong. I cranked the heat up to 104 and felt the heater kick on and push out the hotter water. But still no bubbles.
All the other jest stiil work fine too.
I don't know why it fixed itself, but it did. But now I have to investigate the "no bubble". Last time it happend, the check valves in the Ozone venturi line were shot.
I'll check the check valves and the clear plastic hose that injects the Ozone and see if thats the problem with the bubbles.
I installed a new Ozone maker about 4-5- years ago and perhaps that is bad too. I think 5 years is the life expectancy of the Ozone units.
I was all ready to bypass the flow switch and had figured at the very least I'd have to get a new flow switch and, maybe, a new circulating pump.
But if all I need is new check valves in the ozone injector line it's not so bad. I actually have a spare OEM Ozone ubnit in the bix becasue last time I needed one, I was told Jacuzzi stopped making them so I bought two. Otherwise I'd get a DEL50 Ozone unit.
Anyway... I'll post back what I discover about the "bubble trouble".