The FlowFinder is a powered flow hood that works well in all situations. When the duct pressure is low, it zeros the pressure across the measurement plane very accurately so that system characteristics do not change. All powered flow hoods do this fairly well on return/exhaust flows. The FlowFinder is unusual in that it’s zeroing goes down to 1/100 Pa. Most are only good around zero to about 2/10 Pa making the FlowFinder exceptional where pressures are low or where there is an alternative route for the air to flow. It is also better than the rest at supply flows because it separates the jets experienced in the supply direction from the flow measurement. The flow is then measured by an onboard fan that knows exactly what its inlet pressure is and can determine flow accurately using rpm and pressure after it’s been stabilized.
In difficult situations, the FlowFinder will still maintain its 3% accuracy while any passive flow hood can get 20 to 50% errors. LBL’s study shows this well.
The FlowFinder measures 6 to 326 CFM in full zero balance mode and up to 503 CFM in compensated mode. It is super light and small and can measure kitchen exhaust, HRV flows in tight places. The “Killer” application for the Flow Finder is that it can be used on a sales call with a Blower Door to identify and measure duct leakage to outdoors visually and quantitatively. Just use the Blower Door to pressurize the house to 25 Pa, and if smoke moves at the registers, the Flow Finder will measure it allowing the operator to identify the most cost effective work that can be done on a home.
DM32 smart gauge will display results in any units – no calculations needed!
High-capacity batteries last up to 12 hours. Save hundreds of dollars a year over throwing away batteries!
Losing tools, disorganization, and protecting your electronics from corrosive smoke are no longer a problem with this custom case. Stiff lid acts as a gauge stand and the rubberized base protects from water and mud. Just open, grab what you need and get testing.
At only 7.8 lb (3.5 kg) this fan can be easily carried or held in one hand.
4.9 lbs (2.2 kg) with small flow hood that is used for exhaust only
10.2' x 13.8' (26 cm x 35 cm)
Air Flow Range
(Supply and Exhaust)
5.9 - 323.7 CFM (10 - 550 m3/h) with zero pressure compensation
324.3 - 500.3 CFM (551 - 850 m3/h) with calculated compensation
Air Flow Units
CFM, liters/s, m3/h
Air Temperature Range for display
14 - 122°F (-10 - 50°C)
0 to 100%
Uncertainty Air Flow
(@ 68°F / 20°C)
3% of the reading, with a minimum of 3 m3/h
Uncertainty Temperature and Humidity
0.5°F and 3% RH at 74°F (23°C)
Repeatability Air Flow Measurement
Better than 1%, with a minimum of 1.8 CFM (3 m3/h)
Resolution Air Flow Measurement
0.1 CFM,1 m3/h, 0.1 liters/s
About 12 hours while measuing at around 45 CFM (75 m3/h)
4GB micro SD card, USB adapter, SD adapter
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