Purpose of this plug?

[MacPlumber2944]

This could be a pressure relief valve, I'm not sure. Anyway, it's a Moen, and started spraying water outward.

 

[Caduceus]

I don't recognize what it's even used for. Maybe some more details and photos from other angles.

 

[Matt30]

Anti siphon?

 

[MacPlumber2944]

thanks. the plumber took away the old parts, so no more pics avail. after his installation of a new Koehler unit, there was no flow, so he took off something and found a piece of mangled O-Ring that had been impeding flow. Giving rise to my suspicion that had been the problem all along; blocked line-subsequent spray from this "plug", causing water to accumulate on the countertop and into the cabinet. I would've never figured this out on my own, glad I called a professional.

 

[IFIXH20]

Some of moen old kitchen faucets like the pure touch or one touch had a vaccum breaker. That looks like the vacuum breaker in the old one touch.

 

[MacPlumber2944]

"Old" was used by someone at the plumbing supply, which greatly surprised me. House built in '97. I'd never have considered anything old yet. What does a vacuum breaker do, exactly?

 

[phishfood]

It protects against possibly contaminated water being sucked back into the water supply piping, in the event that a water main somewhere is cut or broken. If a siphon is created on the side of the vacuum breaker that is normally pressurized, it will open and allow air into the piping, and block water from the output piping from flowing backwards.

 

[MacPlumber2944]

Thanks very much.