What is the purpose of automatic drain valves?

Automatic drain valves are essential components in irrigation systems, particularly in regions that experience freezing temperatures. The primary purpose of these valves is to prevent damage to pipes and fittings caused by the expansion of freezing water. When water freezes, it expands, and if this occurs within an irrigation system that has water trapped in it, the pressure can build up to dangerous levels, potentially leading to ruptured pipes and costly repairs.

By automatically draining the system when it is not in use or when temperatures drop, these valves ensure that any remaining water is expelled from the pipes. This proactive approach to system maintenance not only extends the lifespan of the irrigation infrastructure but also helps landscape contractors avoid emergency repairs and maintain a reliable irrigation system.

The other choices, while related to aspects of irrigation systems, do not accurately describe the primary function of automatic drain valves. They focus on functions like watering speed, water flow, and pressure checks, which are not the main purposes of these specific valves.