I have a 2003 Jacuzzi J-310 that I have operated for about 4 years. After initially replacing the temperature sensor (twice now), the heater, the flow switch (about a year ago) and most recently, the control panel, I have an interesting problem.
I get the FL1 flashing signal on the LED display, but when I run the pump on high, it goes out. I have purchased a new flow switch and had intended to install it, but as the nights go by when the switch operates normally, I had deferred replacing the switch.
Recently, I noticed that if I replaced the cover when I was done using it, and if the cover dropped onto the edges of the hot tub, the FL1 signal would flash - fixed, as always, but running the pump on high for a few minutes. Sometimes, none of the buttons on the old control panel would work until I smacked my fist down on the edge. I replaced the control panel and didn't experience any issues for a short time. Recently, just as an experiment, I smacked my hand down on the edge of the tub near the control panel. The FL1 signal flashed on. It still went away if I ran the pump on high.
Last night, as I got out of the tub, the FL1 signal came on and I smacked my fist on the edge of the tub. The LED display read 59 and the heater light came on. I covered the tub and left it be until tonight when I went out to the tub. The LED display read 87 and the heater light was on. I removed the cover and put my hand in the water, it had to be 120 degrees. I turned off the hot tub, waited a minute or so, and turned it back on. The LED display read 100, the demand temperature, then it immediately went to the - - - display, indicating the "Watchdog" software had been activated. I left it open for about an hour to cool, then unplugged the tub and plugged it in again. The LED display read 100, the demand, then started counting down to 87.
Okay. Has anybody had a similar issue? I cleaned and tightened all the slide-on connections on the circuit board this morning (FL air tends to corrode everything) but it's still to hot to plug it back in to test (110F). Before I pull the trigger on buying another circuit board, any help would be appreciated.