I have an old Fafco solar system (approx. 20) years) and I have a check valve that has gone bad, at least I believe that is the case. When the filter shuts off I have DE draining back into the pool. Anyway, I've been told by a couple of people in the field that I need to replace the entire pluming setup ($800.00) because you can no longer buy these check valves. I find this hard to believe.
Does anyone know if these valves are still available and where I might be able to purchase one.