I have a Fleck 5600se system in my household of 7 people. We just installed the system over 6 months ago but recently it started continually running water into the drain. After looking at the manual, it sounds like there is a broken piston(?) or something in the timer. I had a guy come look at it and he indicated 2 things (1 the system would cost more to fix than it's worth and (2 the system is not big enough for my family size.

So my question is if the system is not capable of handling our usage needs and whether or not it should be fixed(I will do the repair myself) or replaced given the symptoms?