When most plumbers think about air in a drain system, they think about venting traps. However, this is not an article about installing an individual vent to serve a trap. It’s not even about different venting systems that could vent several traps. This article is about the necessary air in a drain system and what it’s doing that you may not even know about.
The first trap was introduced into plumbing in 1865 in America, and since then it has been modified to prevent the loss of its trap seal. Some modifications have been great, and others have had a negative
