I'm new to the forum and I hope that someone can help me solve this issue. I recently installed four WSE47 solar panels to heat my pool. The issue I'm having is getting the heated water back to the pool. I've got the panels plumbed in with the lines from my pump. But since the panels work at a lower pressure I've got a valve to adjust the flow into the panels. But what seems to be happening is that the pressured water from the pump is too strong and is making water flow back up the outlet pipe coming from the panels. Since the panels need to have a open breather tube the water is pumping out of the breather tube. I installed a back flow valve in the panel's outlet tube to prevent the water flowing back up, but now it seems the water trying to flow up is too strong and won't let the back flow valve open so none of the heated water is making it's way back to the pool. Any ideas??