I have recently plumbed roof mounted solar panels into my pool system. Everything was fine but after reading, I found that I needed a check valve to prevent solar panels from flowing back into the filter. Today I plumbed a pentair check valve into the system. I turned the system on and everything was working fine. I turned the system off to make sure the solar panels drained ok and at that point my filter gurgled and my pump basket water bubbled and drained. I turned the system back on and the pump had lost its prime and the filter started leaking in a half dozen places when prime returned. I turned the system back off and checked the o rings in the filter. Everything was ok so I reassembled system turned it on and no leaks. I then turned system back off did not open filter, waited 10 minutes and turned system back on and once primed the filter leaked a lot around the lid again. The only change from yesterday when it was working fine is the check valve. The valve flow is correct, so I am at a complete loss. Until today the filter has never leaked and the pump has always kept its prime. I hope I put the check valve in the correct position. Any help or insight would be great. Thank you. 
