ballengerb1
Oct 9, 2007, 02:10 PM
An S trap looks like two P traps installed back to back. It is in the shape of a letter S laying on its side. S traps are no longer code in most areas but can still be bought as replacements for old grandfathered installations. They can tend to siphon and not keep the proper level of water to maintain a seal from sewer gas.