Plumbing Vent Plug?

Not familiar with what these are or used for. I could not get close enough to read the tags fully, what part I could read is “must inflate plug to the pressure on plug” I have tried to do a search for vent plugs but no luck with seeing anything like thesesDSCN4949

That looks like a test plug for testing the DWV system. Obviously, the plumber is testing with air.
If that was left in there by mistake, the vent system must not work too well.


That’s what I thought but I haven’t seen this type before. All drains worked just fine. Usually I see the cap left on at the top of the vent above the roof line. These plugs may be only for the pipe fittings installed in the attic which would allow normal air intake at the roof.

Thank you sir

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I wonder why the toilet gurgles and bubbles like that? :rofl:

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He though it was something he eat. LOL!!!

What are the extension cords for?

I think they are tubes used to fill the plug with air, stopping the air passage, to test the system. But, I’m not sure since I’ve not seen them before.

It’s an extension hose to reach the ball. They us a hand pump.


Have never seen these used like this. I’m guessing this was on a multi-level house and the plumber did not want to or could not go onto the roof to fill the D/V by hose. These are normally used at the cleanouts down low and water is used to fill the vents at the roof to test the vents and drains. Yep looks like the plumber forgot to take these with him when he left.

They may have air pressure tested it. I’m used to seeing them temporarily capped above the roof line, then the cap gets cut off after the testing (often times they miss one or more).

In any case, the test plug should be removed and the vent cleanout opening capped before the structure is occupied.

I think this is SCHEDULE 40 PVC DWV FITTING ASTM D2665

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