I go to Lowes and Home Depot and pick up the fitting I want. I would put a sealant in the joint if necessary.
Easy first try is to loosen the union nut and clean the threads. Then apply light oil and retighten. You did not put any sealer on the union threads did you? that is a no no. Does it have brass seals inside the union joint? If not replace it.
Bill D
A union does not rely on sealant in the union threads to keep from leaking, it is a metal to metal seal. The big nut is just there to draw the two seats together. Any imperfection in the seat will cause a leak.
NOW you tell me...
I would just use your Sharkbite fittings as your union and get rid of everything on the right side. You probably aren't disconnecting the pump for years anyhow unless they fail regularly.
Yup, I admit I remembered wrong.
Pipe dope was for my black iron gas fittings.
Sharkbite will make your problem vanish.
Young enough to remember doing it;
Old enough to wish I could do it again.
Ok, by now you know I'm not even close to being a plumber, one of the pex connections is leaking slightly, I'm close to giving up.
Assumption is the mother of all screw ups
Anonyms
My fathers solution was rubber hose. It has to be like radiator hose with internal support so it does not collapse under suction. cars often have a loose spring inserted inside normal hose. The spring is like 3/4" between loops. For your use I would use stainless or brass wire to make a spring.
Bill D
3/4 pex is only like 1/2 npt pipe. You should have used at least one inch pex if you are needing 3/4 npt. Even garden hose would flow better.
Bill D
Are you sure they are leaking and it's not just humidity condensing on the metal? If it's just for a week or so I wouldn't worry about it unless the leak is so bad the catch pan is filling too fast.
The end of your PEX fitting has to be absolutely square, clean and free of any abrasions before inserting into the push to connect fittings you're using. Cut that section of PEX out, pull it from the fittings, remove the union and go directly into the end of that check valve. If this is all just temporary, it's easier just to cut through the PEX and re-insert a new piece when the time comes to re-work everything. As I'd mentioned, the vibration from your jet pump when it runs will cause the union to leak if it's that close to the inlet end of it. I've gone through this very install with that same Pentair Sta-Rite pump and a metal to metal union connection is not going to remain water-tight there.
This should not be leaking unless the pump is not running.
Bill D