Series-VFC-VFCII

Supported Applications

The Dwyer Series VFC Visi-Float® Acrylic Flowmeters are direct reading, precision machined flow meters designed for visual measurement of compatible gases and liquids. The series is utilized in applications including medical equipment, laboratory equipment, air samplers, gas analyzers, pollution monitors, chemical injectors, cabinet purging, remediation systems, and osmosis skids.

Operating Conditions & Performance

The Series VFC flowmeters operate within a temperature limit of 100 psig (6.9 bar) @ 120°F (48°C). Accuracy is specified as 2% of FS with high repeatability enabled by precision machined tapered bores. The typical scale length is 5" for the series, featuring hot-stamped direct reading scales that eliminate conversion requirements.

Popular measurement ranges documented in the range chart include:

• Air (SCFM): 4 to 25 SCFM Air, 5 to 50 SCFM Air, and 10 to 100 SCFM Air.
• Air (LPM): 100 to 700 LPM Air, 200 to 1400 LPM Air, and 300 to 2800 LPM Air.
• Water (GPM): .5 to 5 GPM Water, 1 to 10 GPM Water, and 2 to 20 GPM Water.
• Water (LPM): 2 to 20 LPM Water, 4 to 40 LPM Water, and 10 to 75 LPM Water.

The series meets the technical requirements of EU Directive 2011/65/EU (RoHS II).

Installation & Media Compatibility Notes

• Mounting: Mount in a vertical position with inlet at the bottom and outlet at the top.
• Torque Limit: Maximum recommended torque is 10 ft. (lbs) (13.56 newton (meter)). Hand tighten only; do not overtighten fittings or piping into meter.
• Incompatible Media: Avoid locations with strong chlorine atmospheres or solvents such as benzene, acetone, carbon tetrachloride, etc.
• Vacuum Service: Any flow control valve used must be installed on the discharge side of the flowmeter.

Configuration Options

The series consists of two basic styles: VFC and VFCII. Both feature bodies cut and precision machined from solid, clear acrylic blocks with a white background for float visibility. Wetted materials include an Acrylic plastic body; Buna-N O-rings (Fluorelastomer available); SS metal parts and floats; PVC fittings on the VFC; and Acetal thermoplastic fittings on the VFCII.

Process Connections

The series supports 1" NPT connections in various configurations:

• VFC Models: 1" female NPT (FNPT) back connections. End connections are optional.
• VFCII Models: 1" male NPT (MNPT) back connections. End connections are optional.

In-line end connection options include 1" FNPT and 1" MNPT configurations, identified by the -EC suffix in model numbers.

Options & Accessories

• -BSPT: BSPT process connections.
• -FDA: 316 SS float and guide rod (only available on VFCII with fluoroelastomer O-rings).
• -NIST: NIST traceable calibration certificate.
• -VIT: Fluoroelastomer O-rings.

Key Product Differences

The primary distinction between the two styles is the fitting material and thread gender. The VFC style utilizes PVC fittings with 1" female NPT back connections, while the VFCII style uses Acetal thermoplastic fittings with 1" male NPT back connections.

Model numbers follow the format Series-Range No.-Option (example: VFC-123-EC). The -EC suffix denotes an in-line end connection configuration. Range numbers correspond to specific flow capacities for air or water as listed in the range chart, with separate series of ranges available for SCFM Air, GPM Water, LPM Air, and LPM Water.