Dry Pipe Systems
A dry pipe system is similar to the wet system only the piping and sprinkler heads are filled with compressed air or nitrogen at all times. In the event of a fire, sprinkler heads activate based on their temperature rating, the dry pipe valve opens from a closed position allowing the air to run out and then water enters the system and extinguishes the fire. This type of system is best suited for areas where freezing occurs.
Commonly used in attics, freezers and unheated areas of buildings