Teflon tape on unions ?
 

Should i be using teflon tape on the threads of unions ?

not on the union threads, you would only use teflon tape on the connecting pipe threads if its a threaded union.

It's a union that's glued to pvc pipes on both sides. I was asking about the threads that join both unions together. Just want to make sure i don't have any leak .

Still think i shouldn't use teflon tape there?

No, if you use teflon tape there is more chance the union wont seat properly, it should work just fine on its own without anything, technically, if there is ever water in the threads of the union it has already failed.

PVC unions should have built in rubber gaskets. That provides the seal, just make sure it's hand tight. If you add tape it won't function properly

Yes it has a o ring on it. Thanks for the help :)

FWIW I have always put about one loop of teflon tape on mine. Not for any sealing properties, but I have found it lubes the threads a bit and make it easier to hand tighten and take apart. Never had a leak in many dozens of them done this way.

Maybe some liquid teflon ? Would this be ok and help with taking it appart ?

Never need teflon on unions, the gasket does the sealing. Some people use A small amount of silicone grease but it is not necessary and could cause problems with the gasket sitting properly.

Ok then. No teflon it is LOL Thanks a lot everyone :)