Where do high suds pressure zones frequently occur?

High suds pressure zones are commonly associated with changes in direction within plumbing systems. When water (or liquid carrying soap and other agents) flows through pipes, it encounters resistance at bends, elbows, and fittings. These changes in direction can disrupt the smooth flow of liquids and create turbulence, leading to increased pressure in certain areas. This phenomenon is particularly notable when the angle of the change in direction exceeds 45 degrees, as the turbulence generated is more significant and can cause problems like suds or air pockets forming in the system.

In contrast, straight sections of pipes generally maintain a more consistent flow without significant pressure fluctuations. The lowest point in a system typically serves as a drainage point for gravity flow, and high suds pressure zones are not concentrated there. Similarly, while the base of stacks can experience different pressures due to vertical movement of fluids, these areas do not exclusively represent high suds pressure zones encountered in typical pipe changes. Therefore, areas where high suds pressure tends to build up are most frequently located at every change in direction greater than 45 degrees.