What is this?

[Amy V]

Hi there,
Curiosity got the best of me. I'm assuming most battery vents are passive. Never seen a lever attached to one before. How is it to be used? Not mentioned in owner's manual and SMB technician said he didn't know.

[Amy V]

Back of closet shot

[marret]

Me either. Looks more like a drain pipe rather than a vent. I assume you confirmed the vent and positively traced. What type of battery(ies)? Could be closed if not needed.

Your second post photo looks like a water line.

[Twoxentrix]

I have a vent (looks identical) mounted on the outside of my Van, and it serves as a water line vent & overflow for my sink.

[REF]

That looks like it could be a diaphragm pump at the back of the closet with the handle on it, where does that line terminate at the back of the closet?
Could be that the van had a different toilet installed at one point and that was used as a pump or flush out?
Where does the “Y” go to that’s behind the toilet? Anything under the van at that junction-Water tank? Grey water tank? Waste tank?
Could it be a manual water draw fill?

[gahamby]

That last shot is a bilge pump.

[daveb]

Originally Posted by Twoxentrix

I have a vent (looks identical) mounted on the outside of my Van, and it serves as a water line vent & overflow for my sink.

Same here but mine is not mounted so high up. It's mounted at the level of my sink drain. Doubt the OP's setup has anything to do with overflow at that level. The hand operated looking bilge pump makes me wonder if it moves vapors if it actually goes to that vent. Seems more orientated toward a black water tank or maybe a vent for a composting head???

[Twoxentrix]

Originally Posted by daveb

Same here but mine is not mounted so high up. It's mounted at the level of my sink drain.

Yep - That was a little dumb of me - I didn't even look at the location in the pic.

[arctictraveller]

That is definitely a hand operated diaphragm pump normally used to pump water

[Amy V]

Good questions. I got under the van and indeed it does terminate near my current black water tank, where it is capped and bolted. There is one long pipe to that point. The gross news is that when I went ahead and pulled the lever today, I can hear water. I guess I'll get my mechanic to open the cap and then---look out below.