The whole thread for my previous PVC joint post seems to have been lost so I thought I would recap a little and give you all an update before moving on to my new question.
I am installing an AutoPilot Total Control system myself. Installing the manifold was tricky as there was very little pipe between the heater and where the return pipe went into the ground. I had a lot of trouble getting the final joint together before the glue locked up, only got it in about half was and slightly angled, and was worried that it might leak. A couple of people told me that it would probably hold, and indeed it seems to be holding. Meanwhile several other things have gone wrong.
I left our solid pool cover on while doing the rest of the spring startup process, hoping to test the joint with the pump running. I don't have the equipment to do an air pressure test, and it is time to open the pool anyway. We bought the house in the fall and had a pool service close the pool. Then I spent the winter reading up on how to handle the pool myself.
I found two drain plugs in the pump strainer basket. One fit nicely into the side of the pump, I'm fairly sure the other one has to go into the heater as there was an uncapped hole in the heater that seems to match the drain location in the heater manual. The problem is that the plug doesn't fit in the hole. The hole was full of rust (or something gritty that looked rusted) and I spent some time with Q-Tips and a toothbrush working lots of rust out of that hole. Still the plug just spins, won't go into the hole, and the threads won't catch at all. It is as if this is a plug for a slightly larger hole.
It didn't seem likely that the people doing the closing had misplaced a drain plug *and* I had missed finding a hole, but to double check I decided to turn on the pump. Sure enough water comes spraying out of the heater and it also comes spraying out of the ground right next to a pipe near where I had been working (but not the pipe I put the manifold into). That was it, two leaks. Digging up that pipe revealed an elbow split in half right through the body of the elbow. I spent today finishing digging that out and replacing it.
That leaves the drain hole in the heater and the plug that won't fit. This has me totally stumped. There is nowhere else for the plug to go, water didn't come out of anywhere else, yet the hole is just a tiny fraction too small. I ordered a replacement plug, which won't come for several days, but I can't see how I could have the wrong plug. I figured the rust was from draining the entire heater coil through that hole. The PH was 6.7 when we bought the house. I fixed it right away, but who knows how long it had been there before we moved in. The heater doesn't leak (yet), so I figure the rust could be left over from then. But that doesn't explain why the plug won't even start to thread in.
I have no clue what to try next.