I'm finally getting around to replacing my irrigation systems back
flow safety and had a question or two.
Originally I had two atmospheric valves on my irrigation supply line.
I've now bought a pressure vacuum breaker. I have everything pieced
together and ready to solder.
1) The old setup was all soldered together, no easy break down. I had
to cut an elbow to get everything off. Does it matter if I solder it
all together again or should I put a coupler in there?
2) Assuming I just solder it all together as is how will teflon tape
on a threaded male adapter hold up to the heat of soldering the other
end of the same adapter?
Dunno what a "coupler" is. What you removed, you can replace, with
the challenge of melting solder while placing fittings. Always: shine
the joint faces, and liberal flux.
What I'd use: sweat unions, to enable quick disconnect of sections of
tubing. Then you likely don't have to concern yourself with some
I've had taped threaded joints near sweated joints many times, with no
failures. Heat it just enough to get the solder to flow, of course.
Yes, I found that out last night. After soldering the pieces together
and turning on the water I found one small leak in a sweat joint that
I figure I could have just heated again to seal but then realized one
of the two threaded joints was leaking. I was pissed, as I have to
pull it all apart and try again. Guess I'll learn to sweat a joint
better, it didnt work quite as easily as I thought would. A couple
joints sucked the solder right up but one or two didnt seem to work to
well, fortuneatly only one leaked.
Is there a better sealer to use? One that will take the heat better?
Is there some type of sealer I can just paint onto the threads that
will seep in and seal it?
Most likely one of two causes--
1. If old work, some residual water is preventing quick heatup.
Solution--drain better or if can't, the old bread trick to act as a
sponge is always possible.
2. Missed getting one side or the other of the joint really clean and
fluxed. Solution--clean and flux.. ( Doh :) )
Don't know what threaded connection you're talking of...if it's a
sweated union, as an earlier poster recommended, the threads have no
function in sealing the joint.
Its a threaded male adapter on one end to thread into the vacumm
pressure valve and a female sweat union on the other side. The sweat
joint got soldered just fine, just enough to destroy the teflon seal
on the threads...
The previous plumbing had what looked like a grey liquid seal on the
threaded parts. What would this be? Would it stand up better to the
Plumber's "dope" -- thread sealant. Will probably be a little more heat
resistant. If you got the parts arranged in an optimum order, you
should be able to do all the soldering first, then put the threaded
Oh, one aside...where did you get the pieces-parts? I've found a lot of
the Chinese junk from the local Ace Hardware and equivalents to have
such sloppy thread tolerances it wasn't possible to tighten them no
that reminds of a funny trick I play on my girlfriends all the time, I
cruise by the plumbing supply house and send them in on an errand, I tell
them to tell the guy at the counter that "my boyfriend needs some dope"
they think I am crazy!
After pulling everything apart, cleaning it and resoldering, I finally
got it right! It really pays to think about how the pieces go
together. Wish I would have put more thought into it the first time,
would've saved me a couple hours of heating, cleaning and sanding
HomeOwnersHub.com is a website for homeowners and building and maintenance pros. It is not affiliated with any of the manufacturers or service providers discussed here.
All logos and trade names are the property of their respective owners.