In the last 6 weeks:
1. Spider gasket failure in the multiport valve causing flow errors. No big deal, that happens.
2. Found that because I heard water trickling in the front yard one day. Investigated and found water flowing at the pool plumbing air gap / backflow preventer hidden in some shrubs. Multiport was set to Filter so there shouldn't have been any flow.
3. But I also discovered that the top and bottom PVC piping on that waste water run had moved out of alignment. The water flow was just going into the ground next to the house, not into the bottom pipe. Had to dig out both pipes a couple of feet down through difficult clay soil to get enough play in the PVC pipes and line them back up again. Had to McGiver some big shims out of cans packed with clay to help wedge them back into alignment. Hot and sweaty and muddy but it all worked out. Did the spider gasket next. Two problems solved.
4. Hoped the spider gasket was also causing my third problem, a recent DE leak. But no such luck. Disassembled the FNS and checked everything in bright sunlight. No visible issues. Maybe the standpipe o-ring? Changed that. Reassembled and restarted. More DE. Disassemble and reinspect everything carefully again. The way they manufacture the manifold, it has a few seams that overlap in a way that you can't put your eyes on every surface that could possibly fail. That seems like the most likely cause. So I buy and install a replacement manifold even though I can see no cracks. Fortunately, problem solved. Good times are finally here.
5. The next week my 7+ year old SWG dies. Oh well, stuff happens. At least SWG swap outs are easy. New one comes in and works like a charm. Problem solved.
6. 10 days later the new SWG dies. With y'alls help I test the voltage output on the IpH and it looks perfect. Pentair sends out a warranty cell quickly. I install it. Ready to reach the finish line. Power the system up. The new SWG is unresponsive. Turns out the IpH had the known connector failure problem. The "no load" voltage testing I did looked good but masked the problem. Okay, stuff happens.
7. With a lot of help and some good luck, the WAGO and welding fix works. I flip the switch and the warranty SWG springs immediately to life. Fantastic!
8. I bother to take out the warranty SWG and retest my original replacement SWG to see if it was going to run now too. Nope. Deader than a bag of hammers. So that really was bad luck. But I get a free replacement flow switch out of the deal and it's great to have everything fixed. Time to kick back and relax.
8. One week later, this leak comes along.
Fun hobby.