This is new work. It is leaking at 2 places, at the spigot and at the shutoff valve. Wondering the best foolproof way to try this again and this time with no leaks.

This is for a sprinkler system.

Upper leak is where the brass spigot is connected to a short iron nipple which is screwed into the plastic female fitting. Teflon tape was used. The glue joint is good. A plastic spigot, with all glued joints, would be fine, if that is the best way to go.

The lower leak is where the female threads of the brass valve attach to the male threads of the plastic fitting. Teflon tape was used. I originally had a plastic shutoff valve here, glued to plastic pipe. This worked fine until the valve broke and I wanted to replace that connection with a better valve. So I went to brass. Maybe this would work OK but is just not tightened well enough. I also used teflon tape and maybe that was a mistake.

Lower connection on the shutoff valve, brass-to-plastic, is not leaking.

All input greatly appreciated.

Gary

both leaks

 

You need to use a generous amount of TFE paste on the threads, not just Teflon. (Any sealant like Rectorseal T plus 2 will work) And you need to be very careful tightening brass into PVC (or vis versa) because if you get it too tight it will crack the PVC.