chainXzero
Active Member
I was just pondering how does the vent pipe work and what are it's main functions? Do gases/air travel both in and out of the pipe?
Main house trap vent pipe
- Thread starter chainXzero
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I was just pondering how does the vent pipe work and what are it's main functions? Do gases/air travel both in and out of the pipe?
Yes gases/air travel both ways as indicated by the two headed arrow on that line. That kind of “whole house trap” dates back to the time before individual traps were required for each plumbing fixture. It has been prohibited by the building codes for many years.
House
House
House traps are obsolete and never used any longer. Most have been removed during service calls. I haven't run in to one in 30 years.
Vent terminations are required to be vertical through the roof.
Vent terminations are required to be vertical through the roof.
chainXzero
Active Member
Would any issues/problems occur if that vent pipe became clogged or obstructed?
turdchaser2000
Well-Known Member
Yes, problems/issues could occur
Plumbing codes change based on better designs, and many better designs are based on issues/problems that occurred in plumbing installations. As no current codes even allow a house trap today, they obviously caused issues/problems.
chainXzero
Active Member
Thanks guys. I guess what I was wondering most is what can happen if that vent pipe becomes obstructed? I own a home with such a plumbing set up and I am trying to educate myself on the way these things work.
Some AHJ still require house traps, aka Building Traps.
Most likely nothing would change if that vent clogged if you have another vent in the system.
If that was the only vent then you’d be flushing into the equivalent of a sealed container and the air couldn’t be displaced. It would cause poor flushing and bubbling in other traps. Air burping.
It’s on the wrong side of the House trap to prevent siphoning, so that’s not the vents purpose.
