What is the primary purpose of a dry sprinkler?

The primary purpose of a dry sprinkler is to keep water out until it is needed. This type of sprinkler system is designed for environments where the risk of freezing poses a significant threat, such as unheated buildings or areas exposed to cold temperatures.

In such systems, the pipes are filled with air or inert gas instead of water. When a fire occurs, the heat activates the sprinkler head, allowing the air pressure to drop, which opens a valve and permits water to flow into the system. This design prevents the water from sitting in the pipes and potentially freezing, which could lead to pipe bursts and system failures.

While other functions like assisting in system pressurization or preventing freezing might play a role indirectly, the fundamental purpose of a dry sprinkler is indeed to withhold water until the system is activated by heat from a fire, thus ensuring reliability and safety in colder conditions.