B. STANDPIPE SYSTEM
The models URFA-25-2.5 and URFA-20-2.5 valves are most commonly used in standpipe
systems. The URFA-25-2.5 valves have a male hose thread outlet for connecting to fire
suppression hose. When hose racks are used, the URFA-20-2.5 can be utilized along with a
special hose nipple for support of the rack. The URFA valves are Listed by Underwriters
Laboratories as Standpipe Equipment Pressure Reducing Devices (VUTX). Requirements for
installation of pressure reducing valves in standpipe systems are given in Section 5-8 of NFPA-
14, Standard for the Installation of Standpipe Hose Systems, 1993 Edition.
INSTALLATION REQUIREMENTS
A. AUTOMATIC SPRINKLER SYSTEM
1. To permit easy replacement or repair of valve, pipe unions or rubber gasket
mechanical couplings should be installed immediately upstream or downstream of
each URFA valve.
2. A relief valve of not less then ½ inch size is to be installed on the downstream side
of each URFA valve
3. Pressure gauges are to be installed on the inlet and outlet side of each pressure-
reducing valve
4. Valve adjustment setting should be selected to provide an outlet pressure not
exceeding 165 psi at the maximum inlet pressure
5. Upon system completion, each Valve must be tested under both flow and no-flow
conditions to verify that static residual outlet pressures and flow rates satisfy system
design requirements. See Section 8-2.5 NFPA 13 for more information on
mandatory flow and no-flow test requirements.
B. STANDPIPE SYSTEM
1. The URFA-25-2.5 can be used for both Class I and Class III service.
2. NFPA 14 requires that hose valve outlet pressures for Class I and Class III service
be no greater then 175 psi. and no less then 100 psi. When permitted by the
authority having jurisdiction, pressures less then 100 psi may be allowed, but in no
cases shall the valve discharge pressure be less then 65 psi
3. Upon system completion, each valve must be tested under both flow and no-flow
conditions to verify that static and residual outlet pressures and flow rates satisfy
system design requirements. See Section 8-5.5 of NFPA 14 for more information
on required flow and no-flow testing.
CONSTRUCTION & OPERATING PRINCIPLE
The URFA is a field adjustable pressure-reducing valve, which utilizes a hydraulic piston and
cylinder assembly within the valve lower bonnet to allow the valve to self-throttle in response
