What is the recommended auxiliary drain size for water trapped greater than 50 gallons?

The recommended auxiliary drain size for water trapped in a system that is greater than 50 gallons is indeed 1 inch. This size is considered adequate to effectively manage and drain such volumes of water, ensuring that the system remains operational and reduces the risk of water damage or system failure.

Using a 1-inch auxiliary drain allows for sufficient flow capacity to handle larger volumes, which is critical in systems where water accumulation could lead to functional issues, such as increased pressure or potential leaks. A drain that is too small may not allow for the rapid evacuation of water, which can lead to the aforementioned problems.

In contrast, a smaller drain size, such as ¾ inch, may not adequately handle the excess water, while a drain size larger than 1 inch, like 2 inches, might be unnecessary and could complicate the system without additional benefit. Therefore, the establishment of 1 inch as the recommended drain size for this specific condition ensures both efficiency and reliability in sprinkler system design and maintenance.