Teflon thread tape on the threads is not where the seal is made on those check valves.
I did not try o ring lube. It seeps up every so slightly. I cannot go any tighter. Im going to shut the valve below and drain one side and take it apart. I dont know what else to do. Thank you for the reply!
I do agree that they will not seal 100% in a reef environment but they still will stop a surge backwash during a power outage. Your sump still needs to be designed to handle the full back siphon potential that could happen over an extended outage.
Thank you, I will one the other valve. The Teflon worked perfectly. It was the tiniest of leaks but still leaking.Take the o-rings completely out of the check valve and rub a good even coat of silicon O-ring lube on them and reseat them. They should seal then.
This is why mechanical siphon breaks are employed, such as the drilled plumbing I described above! Break the siphon as soon as it starts, and all that! (This means you only need sump volume for the drains trickling down the display to the bottom of your weir teeth)
This only applies to return pumps in parallel on a single return plumbing line! if each return pump has an independently plumbed return line, no check valves are necessary!
I disagree with this. Even if they are independent the water will still flow back down the other return line acting as a drain right back into the return chamber and just get pumped back up the other return line reducing the amount that goes through the sump filtration.
You put teflon tape on the threads? Is it still leak free this morning? I would think doing this would just cause it to leak around the top of the nut then instead of the through the threads?
This makes me think there’s a chance that it’s over-tightened and leaking because the o-ring is crushed. O-ring seals need to be tightened a certain amount, too tight and little gaps get introduced
