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Diagram of Class A Wiring

Free PDF Diagram:

Fire Suppression
Dry Sprinkler System Valve

See how the Dry Sprinkler System Valve works.

It keeps out the water, but how does it turn on automatically?

To prevent the pipes from freezing and breaking, air pressure holds a clapper valve shut. When the thermal fusable link on a sprinkler head breaks, the head lets the air out and water flows to the head.

The Diagram Shows:
  • The normal conditions and the discharge conditions for the Dry System Valve.
  • How the pressure gages are connected to the valve.
  • Where the supervisory air pressure swtich is located.
  • Where the alarm pressure switch is located.