Hi, I'm installing a solar heating system to my pool. I have a 24' round Intex with a Hayward C50 DE filter. DO I really need a check vale between the filter and the inlet line for the panels? My panels are installed next to the pool and are about 3-4' higher than where the filter is. I do have a check valve installed on the output line for the panels but was wondering if the other one is really needed. I'm installing something similar to the system explained on the link below: http://rimstar.org/renewnrg/solar_pool_ ... mation.htm
Looking at thhis diagram, I only need one check valve. Anybody care to comment?? Thanks!!