I’m am finding more and more of failing PEX connectors. Last one is Vanguard Vanex brand. In doing some research I’ve discovered some localized lawsuits but no national recall. One client recently said the plumber consulted told her the connections should not have been brass. I think that was a doubtful answer to the issue. Anyone else seeing this or know of more information regarding this issue?
Is corrosion a failure?
Dezincification
When brass pipe fittings are manufactured, zinc is added to the copper alloy to increase the strength of the brass. Because the corrosion of brass is dependent on increasing amounts of zinc, it is recommended to keep the zinc content low (15%-19% of the total alloy). To reduce cost, manufacturers have been turning to high zinc levels (35%+) in the alloy. (Snyder 2011)
When water flows through the fitting, the zinc, due to its weak bond strength at the molecular level, leaches from the brass and creates a powdery buildup. This process is known as dezincification. This buildup can cause a blockage within the fitting. The powdery buildup and blockage can be seen in the video to the right, used with permission from SageWater. (Zinc Oxide Buildup 2009) Also, when the zinc leaches from the copper, it leaves the copper very porous and thus mechanically weak. This weakness can cause the fitting to leak and possibly rupture. (Snyder 2011)
Not a immediate failure per say however I don’t know what is normal corrosion and what may be dezincification leading to failure. Given that PEX is having some issues with connectors this is looking like the poly pipe connectors issue all over again.
There has been a class action settlement for Kitek (may have spelled it wrong)
that deals with this very issue
Hope this Helps
Cheers
This is an example of the fittings I’ve been seeing. The brass fittings look a lot like the ones used for Polybutylene.
Cant say Ive laid eyes on them here in my area. So far all brass. The plastic looks like it could become an issue with getting brittle as it experiences heat from the attic all the time.
Couldn’t read the manufacturer on the block, so maybe this is related?.. http://terrylove.com/forums/index.php?threads/vanguard-pipe-with-ipex-fittings.16182/