I guess the high 90's heat here in the Northeast was too much for my expansion tank, as it has begun to leak (that's putting it mildly.) I believe it's painted copper or copper alloy. Has anyone had the need to fix one of these - I understand that they aren't readily available, and I'd much rather fix anthing that's fixable anyway. I was wondering if it could be sweated like copper pipe? Any feedback, as always, would be appreciated. Gary