About six months ago, I had to replace the tank on my well. On the output side, I used a 1 1/4 threaded x solvent PVC union, then a 1 1/4 x 1" PVC bushing and then 1" PVC pipes and fittings to the house. At the time, the adapter leaked at the threads of the union and the tank bung. I went through three unions before I finally got one that didn't leak.
Last night, water is pouring out from under the well cover. This morning, I pull the cover and find that it is leaking again at the union to bung interface. It was leaking so bad, I thought the union had cracked but when I removed it, there were no cracks.
So i got a 1 1/4" to 1" threaded galvanized bushing and screwed it into the bung, then I used a 1" threaded x solvent PVC union and it seems to be holding.
But if it starts leaking again, I am thinking of using Ultra Gray RTV instead of teflon tape on the threads. any reason why this is not a good idea? Has anyone used some type of RTV on a particularly persistent leak?