What is the minimum air pressure typically required in a dry pipe system?

In a dry pipe system, the minimum air pressure is crucial for ensuring that the system remains operational under various conditions. Typically, the minimum pressure required to effectively keep the pipes dry and to avoid the accidental release of water from the sprinkler heads is around 275 kPa. This pressure helps maintain the necessary air cushion in the system against the force of gravity and any potential backflow.

By keeping the air pressure at or above this level, the system can reliably detect any drop in pressure which would indicate a leak or a discharge event. Such a design is essential for fire protection systems, where the quick release of water must be activated only upon the detection of heat or smoke. Proper maintenance of this minimum pressure is fundamental to the integrity and functionality of a dry pipe sprinkler system, making 275 kPa the standard reference point for operational readiness.