Kitchen sink venting direction

[Luke87]

Hi, I have installed a Saniflo drain water pump in my basement kitchen sink. This drain pump is required to be vented to a 2 way air vent and unfortunately cannot used with an AAV. I have vented the unit and connected it to an existing vertical vent pipe in my utility room. The pump seems to work fine, however my concern afterwards was that I may have installed the vent pipe in the wrong direction. I issue is i had to take the vent pipe up and over an object then come back down on a downward slope connecting to the vertical vent pipe. Would a downward sloping vent pipe affect the air from venting properly? I have attached a picture for reference. Thanks

 

[frodo]

no luke, you can not do that

a vent can only rise away from the fixture it can not dip down

 

[Diehard]

"Would a downward sloping vent pipe affect the air from venting properly?"
The answer is NO.
The main thing is that it has no drops or sags that would trap water.

EXAMPLE:

 

[frodo]

Yes Diehard you are correct International plumbing code allows you to install
like was shown in the picture.

Uniform Plumbing Code does not allow that garbage.
I work and have worked under UPC for years [30plus]
so my answers will always be geared toward that code

In the UPC code to install a vent like you showed in your drawing would require a nod from the plumbing inspector
to install because of structural restraints.

OR.......




The correct way to install this vent would be

 

[Diehard]

Well the way I see it, they both serve the same purpose. And as my old boss used to say, "it meets the spirit of the code."
Not sure why you call it garbage. It works just as well and causes no negative effects. I think if we live long enough we may see the UPC update it's wording on this one.
I've worked in the plumbing field(not as a plumber) around the country as well as a bit overseas, so I've learned to keep an open mind to codes and code officials.

 

[frodo]

UPDATE
I had a chance to talk to the state plumbing inspector and asked him about the wording of


His response was kind of funny. This was the conversation.

What are you tying that vent into?
I said, Another vent
He said. correct.
What does the code say to tie it into?

I said. To drain back to the drainage pipe

He said. Correct
Did the code say to slope it to the vent pipe or back to the drain?

I said back to the drain.

He said
There is your answer

 

[Diehard]

UPDATE
I had a chance to talk to the state plumbing inspector and asked him about the wording of

View attachment 20103
His response was kind of funny. This was the conversation.

What are you tying that vent into?
I said, Another vent
He said. correct.
What does the code say to tie it into?

I said. To drain back to the drainage pipe

He said. Correct
Did the code say to slope it to the vent pipe or back to the drain?

I said back to the drain.

He said
There is your answer

Like I said, "I've learned to keep an open mind to codes and code officials."

You should have asked him if he thought it would make a difference, functionally.

I had one occasion where I sent a State plumbing inspector back to the head of the State Plumbing Board to get his incorrect interpretation straight on another subject.

 

[frodo]

Like I said, "I've learned to keep an open mind to codes and code officials."

You should have asked him if he thought it would make a difference, functionally.

I had one occasion where I sent a State plumbing inspector back to the head of the State Plumbing Board to get his incorrect interpretation straight on another subject.

Actually i did ask him that.
and his answer made sense to me, Functionally? NO
BUT, A vent has 2 jobs, one is to keep the system at equal pressure so the seal on the trap is not compromised
the other is to vent the Methane gas out of the building
hot air rises, and it takes the methane gas with it as it goes
when you impede the path of the gas you create a pocket of methane
Our main job as plumbers is the health and safety of the public
A situation that has the remote possibility of causing harm to the public
is therefore against the code

 

[Diehard]

Actually i did ask him that.
and his answer made sense to me, Functionally? NO
BUT, A vent has 2 jobs, one is to keep the system at equal pressure so the seal on the trap is not compromised
the other is to vent the Methane gas out of the building
hot air rises, and it takes the methane gas with it as it goes
when you impede the path of the gas you create a pocket of methane
Our main job as plumbers is the health and safety of the public
A situation that has the remote possibility of causing harm to the public
is therefore against the code
View attachment 20105

That sounds like it makes sense except that the majority of air flow is going the other way.
That also puts AAV's in a situation of putting the health and safety of the public in jeopardy, I think.
Of course, it also depends on which code one must follow.