What is the minimum height for a clothes washing machine stand-pipe receptor?

The minimum height for a clothes washing machine stand-pipe receptor is determined by plumbing codes to ensure proper drainage and to prevent backflow issues. The requirement of 18 inches is designed to allow for adequate siphoning to occur without the risk of water from the drain line returning to the machine, which could cause contamination.

This height allows the water to flow freely from the washing machine into the drain without creating any negative pressure that could lead to siphoning or backflow. It also accounts for common variations in washing machine discharge hoses and helps ensure that the stand-pipe can accommodate different washer models and their specific discharge requirements.

In summary, the designation of 18 inches as the minimum height is rooted in safety and functionality, ensuring that the plumbing system operates effectively while reducing the risk of plumbing issues.