My sump pit is pumped into the sanitary sewer. (its allowed). There is a AAV close to where it enters the horizontal drain. I assume as it stands now it is not needed. However, I am thinking of sealing the sump pit. I am also assuming a sump>sanitary sewer doesn't need a trap since the trap is created by the check-valve.

Does a sump pump need a vent in my situation?



Edited 1 times.

if you seal the sump pit it WILL need a vent to atmosphere - an aav will NOT work as it only admits air

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"Measure Twice & Cut Once" - Retired U.A. Local 1 & 638

I knew it needs a vent if I seal it to prevent air lock... I think its done with 3/4" pvc thru the cover to the outdoors.

But in regards to drainage, I wanted to confirm it doesn't need an standard vent or an aav to work properly.

I would like to cut the aav out of the system entirely but I fear someone put it there to stop it from gurgling or something.



Edited 3 times.

since there is no sewer gas involved with the sump pump pit, why would you seal it ??
as long as the check valve is working, no gases can come back from the sewer into the house.
no vent is needed where the discharge enters the house main drain.
i'm thinking that if you seal the tank lid an AAV would work as a tank vent.
ground water only seeps into that tank where as a sewer ejector tank receives water from a flushing toilet etc?? so when the pump kicks on it will develop a negative pressure inside the sealed tank and an AAV would relieve that??
of course my friend from SC may be correct ??

"Assuming" any water merely 'seeps' into the pit, and the pit is not actually sealed COMPLETELY air tight, then an AAV would 'probably' work as Packy states.

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"Measure Twice & Cut Once" - Retired U.A. Local 1 & 638

There is a sink upstream of the pump (sink vents thru roof)... Is it likely a sump pump would siphon an upstream trap? Maybe that's why the AAV is there.



ps: my reasoning for sealing the sump is sometimes if the pit has been dry for awhile and we get a hard rain, I get sulpheric type odor which I think is from ground water. It happens the first rain of spring or like today after getting rain for a few days after a dry summer. This odor I know (hope) is not sewer gas because there is approx. 7' of vertical head and the check valve is trapping that much water.



Edited 1 times.

yes

i think he is asking if it needs a vent at the point it enters the house sewer?
the answer to that part is no.