Originally Posted By: mbartels This post was automatically imported from our archived forum.
I came across a plumbing vent for a sink in a basement that did not extended up through the roof. Instead, it went about 5’ up from the slab and had a black plastic cap on it. Cap said In Line vent or something like that. I assume this is wrong but we all know what happens when one assumes.
Anyone out there know what these a for? It can’t be a substitute for a real vent could it?
Originally Posted By: jhagarty This post was automatically imported from our archived forum.
It is a vacuum trap vent. it is installed in locations of poor venting due to distance from the main stack vent. It is commonly installed in this area.
Check with the local municipal code for the service application.
I did not realise it opened and closed with the pressure changes.