Hi I want to tell you what has worked for me believe it or not this is what I have experienced and it works EVery TIME, ok when I get a FL1 code, I take out the filter clean it, then put a hose where the filter goes putting the hose over the screened part using a rag forcing water in the screened part then I put the filter back in if it throws a FL1 code then what I do is PUT SHOCK IN THE HOT TUB that's right SHOCK the heck out of it let it cycle all night and in the morning Bam the FL1 code is gone, I believe the Shock either removes oil, or removes crystals that have formed inside the hoses and the hot tub works flawlessly try it this process has worked for me every time it sounds crazy but it works and I have replaced many flow switches until I have figured out this procedure.
