Brand New Taco Backflow Preventer leaking through center port

Seasoned_Amateur

I installed this LF007M3-QT 3/4 to feed my new boiler. It is leaking a steady drip through the center port. Is it defective? Or have I done something to make it cry?

hot_rod

you have a piece of dirt solder, teflon , something stuck inside

Water enters from the left side the pressure pushes an inner spool against a washer or o ring see the t shape cut away of an o ring? The end of the brass spool contacts that

This closes off the bottom port , If water drips right away, something is lodged in that seal.

They are fairly easy to disassemble and clean out

Should be a strainer on the inlet? That generally catches most any problems?

This is a Caleffi, but they are all similar inside

IMG_9206.jpeg

Seasoned_Amateur

I bet you're correct about the solder. Thanks @hot_rod

Joe Mattiello

is that a Watts? Always willing to help, but I don’t have any experience with that Valve

Seasoned_Amateur

Thanks, @Joe Mattiello. @hot_rod was correct. I got it solved. Much appreciated.

Joe Mattiello

hot Rod is brilliant!!

hot_rod

https://forum.heatinghelp.com/discussion/comment/1827459#Comment_1827459

even a blind squirrel gets a nut, now and then 🤓