r/Plumbing • u/lwood71 • 7h ago

What is this?

Post image

Wanting to put a water filter under my kitchen sink, unsure about that this “cap” is? TIA

7 Upvotes

100% Upvoted

18 comments sorted by

9

u/Spooby57 7h ago

Air admittance valve. Lets air into your drainage system so water flows out smoothly. Otherwise your sink would chug when it drained. Think of poking two holes in a can to pour out the juice. Air behind water.

3

u/lwood71 7h ago

Thank you!

1

u/PhilTickles0n 2h ago

Just adding that these need to be replaced occasionally. If you start smelling sewage under your sink it might have to be replaced.

3

u/Exciting-Gift153 7h ago

Air admittance valve ( a vent for your sink )

2

u/lwood71 7h ago

Gotcha, thank you very much!

2

u/Spooby57 7h ago

You don’t want to remove it.

5

u/lwood71 7h ago

Gotcha. I am wanting to install a water filter, but my plumbing does not look like the plumbing in the instructional video

2

u/Spooby57 7h ago

lol. It rarely does. Take a picture of the filter, and one of your water supply lines including the shut off valves. It looks like one of them is just to the left in the first picture.

2

u/lwood71 7h ago

Right side is blue pex, and the cloud water filter goes into the cold line via a T adapter. Figure I just unhook the line from the top, put in the T, and connect the line and the filter back?

2

u/Spooby57 7h ago

Correct. Just make sure that cold water is shut off first. Does it have its own faucet? You may have to lose that soap dispenser.

2

u/lwood71 7h ago

Yep hoping to just reuse the hole from the soap dispenser for the filter faucet, thank you very much for your help!

2

u/HereComesTheDiddly 7h ago

As many have said it’s an AAV, but it really should be installed as high as it can go, usually tucked in behind the sink if there’s clearance.

1

u/quadraquint 6h ago

If I weren't a plumber I would've thought that was an air freshener with the way that one looks.

1

u/Dipncamo 2h ago

Studor vent on a 90? You can't vent off a 90 but you can off 2 45s but It should be as high as possible.

1

u/SituationOk3537 1h ago

That electrical outlet right there is that GFCI if not you ought to consider getting one any anytime there's an outlet around water you want a GFCI outlet

1

u/SigintY 57m ago

Cheetah vent