OK so this isn't a plumbing forum, but i'm posting in the lounge. This site has a great diversity of knowledge so i feel confident that i can find my answer here.

When plumbing in a hot water heater with PVC / CPVC: every time i put plastic directly to the heater, i have a leak. Can't tighten the fitting without cutting the pipe. I spent an hour on line looking, but couldn't find an answer.

I'm thinking that this time i'll use a steel nipple on the heater, and a coupling to the plastic pipe. This way if I need to tighten a fitting, it's possible.

???