RESIDENTIAL FIRE SERVICE METER

APPLICATIONS: The Hersey Residential Fire Meter (RFM) is specifically designed for use in residential fire protection systems or combination systems that supply domestic plumbing needs and residential sprinkler fire protection service when installed as specified in NFPA 13D or NFPA 13R; (Standards for the installation of sprinkler systems in one and two family dwellings, manufactured homes and residential occupancies up to and including four stories in height). The RFM utilizes Hersey's unique vertical turbine measuring element to measure flow rates comparable to traditional positive displacement meters, yet provides a measuring element that allows suspend particulate matter to pass through the element unobstructed when emergency flow requirements for water are demanded. No other meter provides more flexibility and dependability for measuring water accurately in residential fire suppression and domestic use applications.

CONFORMANCE TO STANDARDS: Each Hersey Residential Fire Service Meter is tested to assure compliance with ANSI/AWWA Standard C701, Class 1. EnviroBrass II® options conform to the NSF 61 Standard.

CONSTRUCTION: Hersey Residential Fire Water Meters consist of three basic parts: maincase; rotor assembly; and a permanently sealed register. Maincases and bottom plates are made of bronze for long service life. Rotor assemblies are thermoplastic, which is dimensionally stable and will not corrode. Retro Thrust® rotor design extends the life of the meter by dividing wear between two points: during low flow the tungsten carbide thrust bearing floats against a sapphire bearing surface; during high flow the stainless steel shaft gently contacts a second sapphire bearing. During medium flow, the rotor floats between the thrust bearings without contact. The measuring chamber is protected by an internal strainer with four times the effective straining area of the inlet pipe diameter. No external strainer is required. Fire service connections are easily recognized by the bright red register collar and lid on all visual read meters. Electronic meters are distinguished by the red collar and lense terminal cover on top of the Translator® register. Optional test ports are available on all 1-1/2" and 2” meters.

REGISTERS: The permanently sealed register has a unique L seal and heat treated glass to eliminate dirt, moisture infiltration and lens fogging. The totalizing register has a straight-reading odometer type display, a 360&Mac251; test circle with center sweep hand and a low flow (leak) detector. All Hersey Meter models have electronic meter reading systems available for increased reading efficiency ( see Meter Reading Systems ).

OPERATION: Water flows through the integral strainer and into the vertical turbine assembly. There, the direction of the water flow is directed by the hub into the rotor at the precise angle necessary for accurate measurement over the full range of flow rates. No straight pipe requirements apply before or after the meter. The turbine turns freely and rotates in direct proportion to the volume of water passing through the meter. The Hersey turbine operates more quietly than conventional disc or piston meters.

MAINTENANCE: All Hersey Residential Fire Meters are designed and manufactured to provide long service life. The register on all sizes can be replaced without removing the meter from the line. Modular design and economical internal parts allow for inexpensive, speedy rebuilds. Optional built-in test ports make field testing easy and convenient.

CONNECTIONS: Available with external (N.P.S.M.) straight pipe threads (ANSI B1.20.1) on 3/4" and 1" sizes; integral two-bolt oval flanges or internal (NPT) pipe threads (ANSI B1.20.1) on 1-1/2" and 2" sizes.

Model Designation
Residential Fire Meter (RFM)

Sizes
3/4", 1", 1-1/2" and 2"

Standards
Manufactured and tested to meet or exceed all applicable parts of ANSI/AWWA C701, Class 1 Standard. UL Fire Service Approval Pending

Service
Cold water measurement with flow in only one direction

Operating Flow Range
See Catalog PDF below

Accuracy
See Catalog PDF below

Maximum Working Pressure
175 PSI, Meets Hydrostatic Pressure Testing to 875 PSI.

Temperature Range
33ºF TO 100ºF

Measuring Elements
Rotor

Strainer
4 times the inlet pipe diameter of straining surface area with .080 perforations.

Register Type
Straight reading, permanently sealed, magnetic drive with low flow indicator. Remote reading units optional

Meter Connections

1/2", 3/4" and 1" external (NPSM) straight pipe threads, 1-1/2 size and 2" size available with either two bolt flanged ends or internal thread (NPT) ends same nominal size as size of meter

Materials
Maincase - bronze UNSC84400; Rotor assembly - thermoplastic; Strainer - stainless steel; Casing bolts - stainless steel ANSI B18.

Options
Meter case - EnviroBrassII® UNSC89520, Spuds and Spools with test ports on 1-1/2" and 2" meters to accommodate standard AWWA laying lengths, Translator registers and AMR Systems


Toomey Water Services 2007 created and maintained by jra design