Sprinkler Devices

Air Release for Wet Sprinkler SystemsAir Release AR-1

The FM Approved UNITED Fire Systems Model AR-1 Wet-Pipe Fire Sprinkler System Air Release is a device for automatically releasing the trapped air from the high point(s) of a wet sprinkler system.

Trapped air contains oxygen, which, when combined with water, is the primary cause of internal pipe corrosion.  This corrosion can lead to pipe blockage, leaks, and pipe failure.

The FM Approved UNITED Fire Systems AR-1 air release is installed at the system high point(s).  Air is vented until water reaches the internal float valve, which automatically closes the device to prevent water release.


  • FM Approved – Complies with NFPA 13 component listing requirement.
  • Dielectric union – Prevents dissimilar metal corrosion.
  • Ball valve – Allows AR-1 servicing without sprinkler system shutdown.
  • Float valve – Automatic shutoff of outlet when air is vented and water reaches device.
  • Strainer – Protects float valve from particulate matter that could contaminate valve seat.
  • Outlet tubing connection – Provides optional connection for remote draining.



The 2016 edition of NFPA 13, Standard for the Installation of Sprinkler Systems, requires a method to vent trapped air in all new wet pipe sprinkler systems. The language of this requirement is:

7.1.5 Air Venting. A single air vent with a connection conforming to 8.16.6 shall be provided on each wet pipe system utilizing metallic pipe. Venting from multiple points on each system shall not be required.

8.16.6 Air Venting. The vent required by 7.1.5 shall be located near a high point in the system to allow air to be removed from that portion of the system using one of the following methods:

  1. Manual valve minimum 1/2” size
  2. Automatic air valve
  3. Other approved means.


Data Sheet – UFS-700 Rev 2.01 Air Release Model AR-1UFS-700

Architect’s Specification – SSAR-1 Rev 1.02 Model AR-1 Air Release (.DOC File)

Architect’s Specification – SSAR-1 Rev 1.02 Model AR-1 Air ReleaseSSAR-1

Drawing Details – DS-AR1 Rev 1.01 Model AR-1 Air Release (Zip file of .DWG file)

Drawing Details – DS-AR1 Rev 1.01 Model AR-1 Air ReleaseDS-AR1

Installation Instructions – UFS-701 Rev 2.00 Model AR-1 Air ReleaseUFS-701

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