I have a Sweetwater Palermo spa from 2001. I changed the water a week ago. The next day when I looked out at the spa, the temperature reading was exactly where I set it for, but every 5 or 10 seconds I'd get the FL1 message. So I took out the filter and replaced it with a brand new filter. The problem seemed to go away. That was 8 days ago. Today I opened up the spa for a soak and the temperature was still exactly where I set it for. But when I turned on the 2-speed circulation pump to get the jets running on low speed, the FL1 flashed, then went away for about 5 minutes. When I shut off the pump and then turned it on again, I got the FL1 message. Then I turned the pump up to high speed and the FL1 went away.
So temperature is holding, heater does come on, jets are working (air bubbles coming out of them), both speeds of the 2 speed pump work, but the FL1 message just appears intermittently. Any clues what the issue can be? Thank you.