BRANDCO FIELD RESOURCES
Pitot vs Pitotless vs Diffuser Flow Testing
A pitot, a pitotless nozzle, and a diffuser solve related problems, but their names do not describe interchangeable measurements. A pitot samples velocity pressure in a water stream. A pitotless device uses its own pressure-to-flow relationship. A diffuser manages discharge and may also contain a measurement system. Choose the complete arrangement before deciding how to read its pressure.
What each method measures
Pitot testing
A pitot tube senses the pressure associated with water velocity at its tip. The test method combines that reading with outlet dimensions and an appropriate discharge coefficient to determine flow. Position, alignment, stream quality, and the correct outlet measurement matter. A gauge connected elsewhere in the hose measures a different condition; it cannot automatically replace the pitot reading.
Pitotless testing
A pitotless nozzle eliminates the need to hold a pitot tip in the stream. Its designated pressure connection and manufacturer-supplied data establish the relationship between pressure and flow. Use the chart for that exact device and configuration. For example, Hose Monster's nozzle chart distinguishes an open discharge from use with a Little Hose Monster. Similar-looking configurations can require different data.
Diffuser testing
A diffuser redirects or dissipates discharge energy. Some diffusers incorporate a pitot or calibrated nozzle; others simply manage water. Before calling any diffuser a flow meter, identify its measurement element, gauge connection, operating range, and applicable conversion data. A quieter or more controlled discharge does not, by itself, establish the gallons per minute being delivered.
Where Brandco wireless equipment fits
The Pressure Sender Mini can bring a compatible device's pressure reading to the operator through a Universal Remote Display. It measures pressure; the display calculates flow only when the selected flow method and configuration support that calculation. This is useful when the flow device is separated from the valve or work position.
For a hydrant test, the Dual Wireless Water Pressure Gauge set can keep a measurement-hydrant pressure reading and a compatible flow-device reading visible together. Assign each sender to its actual location. Enable flow calculation only for the sender measuring the appropriate flow-device pressure, not the static/residual hydrant pressure.
Check compatibility before connecting
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Confirm the gauge port measures the pressure required by the device's flow method.
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Match the thread, coupling, pressure range, and environmental rating to the installation.
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Use the manufacturer's current chart, coefficient, outlet diameter, and approved configuration.
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Confirm whether the device needs gauge pressure or a pressure difference between two ports.
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Check calibration status and inspect the nozzle, pitot, hoses, and pressure connections.
That fourth check is especially important. The Hose Monster In-line Pitotless Nozzle guide uses differential pressure between the nozzle and a downstream chamber. One ordinary pressure sender on one port does not supply that differential measurement. Do not enable a generic flow calculation and assume it is equivalent; verify an appropriate measurement arrangement with the equipment manufacturers.
Build a repeatable test record
Document the device model, nozzle size, configuration, pressure source, and conversion method before flowing. Follow the approved test plan and discharge controls. Once conditions stabilize, associate the flow reading with the simultaneous system-pressure readings needed for the test. Afterward, preserve the raw pressure and configuration alongside the calculated flow so another technician can understand the result.
Brandco's display settings guide explains how manufacturer, diameter, and coefficient entries affect the calculation. Verify those entries against your specific equipment, and check wireless communication from the actual operating position before beginning.
Frequently asked questions
Is pitotless always more accurate?
No. Accuracy depends on the complete measurement chain: device condition, gauge performance, installation, operating range, and correct conversion data. Convenience and measurement uncertainty are separate considerations.
Can any diffuser be used with Brandco?
A compatible pressure port alone is not enough to confirm a valid flow calculation. Verify the measurement method and settings. Ask Brandco about your exact model before selecting a setup.
Can wireless equipment replace the flow device?
No. Wireless equipment changes how readings reach the operator. The pitot, calibrated nozzle, meter, or other approved flow-measurement arrangement still determines the flow measurement.
Related resources
Hydrant flow testing equipment checklist · Wireless vs analog pressure gauges
References
Hose Monster flow charts · In-line Pitotless Nozzle user guide · Brandco flow-device configuration