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 Slow leak at Viega manabloc port
Author: adkroot (NY)

I just put a new Viega manabloc into service yesterday and 3 of the 8 ports that aren’t in use are leaking ever so slowly. I guess I misunderstood the function of a manabloc having thought they were effective shutoffs for each supplied fixture since support at Viega said they were only “service” shutoffs and shouldn’t be considered actual shutoffs in the sense that they’ll always stop 100% of water to the fixture.
I only installed shutoffs at the toilets. Should I be installing individual fixture shutoffs as well? Home run system.
Thanks, Dan

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 Re: Slow leak at Viega manabloc port
Author: bsipps (PA)

You may have a faulty manabloc I’ve seen hundreds of manablocs with unused/uncapped ports not leak, yes shutoff valves at the fixture is best practice

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 Re: Slow leak at Viega manabloc port
Author: Curly (CA)

I'm not familiar with Viega manabloc but generally speaking unused ports also get a cap.

Yes, each fixture should have its own induvial shut off...manifold or not. Required by code in my area and good practice.

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 Re: Slow leak at Viega manabloc port
Author: sum (FL)

I saw a lot of Viega manabloc leak stories on the internet. Many of them mentioned the problem is worn o-rings. I wonder if these stops can be serviced or replaced whether these o-rings can be replaced.

I do think you want stops near the fixtures as well and having those manifold stops does not mean the fixture stops are not necessary. However not all supply lines can have fixture stops where it's easy to access and practical like supplies to a tub/shower valves.

However I think if the manufacturer saying these are not guaranteed to be 100% shutoff is a cop out. If it's a service stop and you can only stop 90% of the water than you can't service them effectively in some cases unless they think everyone is Sharkbites or ProPress at the other end. They encouraged the end user to use these manifolds with so many outlets one to each fixture so they use lots of extra tubing for home runs yet they can't reliably isolate each outlet?

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 Re: Slow leak at Viega manabloc port
Author: adkroot (NY)

I agree that they shouldn’t be considered 100% service shutoffs is a cop out since Viega’s marketing implicitly touts the benefit of the integrated manabloc shutoffs as making fixture shutoffs unnecessary. They did say that there was no way to replace o rings but I’ve seen search results on YouTube that detail the process.

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