Stink from kitchen grey tank

rhagfo wrote:

ScottG wrote:

enblethen wrote:
Covering the vent, can allow water in the p trap to be siphoned out.

Good point, where else would the air come from...

So maybe just removing the baggy and/or replacing it will solve the issue.

Yep the water draining to the tank needs that air break after or the trap will be sucked dry. Previous owner likely covered as it wasn't sealing any more.

Exactly.......
Air Admittance Valve.....admits air into drain line to break any vacuum which would suck the water right out of 'P' trap

Putting a plastic bag over AAV is one way of stopping stink from grey tank coming back up thru faulty AAV.
Better way is to replace it.

Also if leaving grey tank drain open cause you have trailer on permanent site.....stink could be due to all the stuff left behind and decaying in the hot temps (sloughed skin, hair, body oils, grease, food particles etc.)
Not being carried out by high liquid level....just trickling out