I'm currently installing a double check backflow preventer and code says that it needs to be able to be "spun/turned out" for maintenance if required – this is the valve in question.
Now the pipe that is going into either end of the valve is 1/2" pex and I'm using this 1/2" Brass PEX Barb x Male Pipe Thread Adapter to make the join.
Given that the pipes wont spin, I'm wondering how I make it easy to "spun/turned out" without cutting the pex?
If I spin the value it will alway get tighter at one end… is the idea that I only half screw it in at end to allow it to spin up that thread whilst coming off the other end or should i be using female adapter on the end of the pex and a male/male adapter which can be spun? Or do I just remove the pex clamp at one end hence disconnecting it from the pipe?
I've seen PVC unions which would make this easy but I haven't seen the equivalent for pex.
Best Answer
If you don't want to convert over a copper union to Pex (which would probably require a little pipe sweating), the Pex unions available are pretty cheesy pieces of junk.
Luckily for you, Pex will twist on it's own fitting. I wouldn't suggest doing it very often, but the once or twice you may have to remove that fitting from the check valve for "inspection", you'll be fine.