have a 165 , with single small sink, p trap underneath, grey water tank vent up through the roof. bad smells coming up through the air lock device under the cabinet, do I really need it with the roof vent ? thanks (in the process of rebuilding right now will eventually completely clean the tank )
That's a really good question, i'm not sure. It is code for RV's. They are not like in stick framed homes. I think they stick open for everyone once in a while.
There are two versions, the ones used in rv's are the cheaper ones.
I would replace it, the spring could be weak. You can perchase one at Lowe's, they're cheap. Just unscrew the old one and screw the new one on. The roof vent is needed when draining the tank.
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