On 5/12/2013 10:05 AM, Danny D wrote:
I'm a big believer in doing things the right way, or, at least knowing
what the right way is (so that the next time you do it the right way).

So I ask what seems like a very basic question:
Q: Does it matter which direction I put these 2" PVC unions on?
http://www4.picturepush.com/photo/a/...g/12915207.jpg

The black and white one seems to be mismatched. I learned the hard way
that even though they seem to go together, the threads may not fully
mate, allowing the outside ring to slip when tightened.

Also, if the "O" ring is in the removable part, you will be able to
better keep track of it when it comes out of the groove.

A union that is vertical should have the ring on the upper part. that
way gravity will help getting the threads started.

Otherwise, as stated, not much difference.

Paul