What does a vent system do in plumbing?

The primary function of a vent system in plumbing is to provide a flow of air and protect trap seals. Vents allow air to enter the drainage system, which is crucial for maintaining proper atmospheric pressure within the pipes. This prevents the formation of a vacuum, which could disrupt the flow of wastewater and potentially siphon water out of the traps. When water is drained, the vent stack ensures that air can replace the volume of water, helping to maintain a proper flow and preventing the traps from being emptied. This is essential for preventing sewer gases from entering the living space and ensuring the efficient operation of the plumbing system.