BTMETER BT-846A Pro HVAC Anemometer Measures Wind Speed Flow Temperature CFM Air Flow Velocity Meter with Backlight MAX MIN AVG

works as expected ,easy to use, good software (windows 10 only supported) and is accurate.

I built a hood to go over 2x2 ceiling diffusers In order to more accurately and consistently gather cfm readings throughout our 5,000 square foot facility that has 3 independent furnaces with multiple zone setups, dozens and dozens of vents to test etc.I didn’t have any issue with the battery door cover as others have mentioned. The backlight not staying on is a huge blunder in the design of the display. You constantly have to turn it back on after it times out in like 5-10sec. The instruction manual is terrible. There’s definitely a learning curve in calculating the surface area of your HVAC duct sizing in square inches, converting that to square feet and then entering that parameter into the meter. I also found a 5-6cfm difference in my readings when I used the built in averaging feature of the unit vs me taking a max and min reading of a vent and then deciding that sum by 2 to get my average. The built in averaging function always came out lower for me. But, it was minimal difference. Overall, this meter does exactly what I needed it to do and at a fraction of the cost vs what you’d typically have to spend on something like this. A few hours in the garage building the hood and I can slide this meters fan right into its receiver slot and I used a cell phone holder mount to hold the units display so I could use both hands to hold the hood up to the ceiling diffuser. Not shown in the picture is a 10 foot extension pole so I don’t have to climb up on a ladder to reach ceiling diffusers in our commercial building.Overall, there is a learning curve to use this meter for cfm readings. Basic wind speed is much easier. But if you’re an intuitive person it’s pretty easy to figure out. Happy with my purchase thus far I just wish the backlight stayed on! Seriously, what were they thinking only having it stay on for such a short amount of time. So stupid.

I’m not a pro, so probably don’t have enough knowledge to evaluate this device fully, but it seems to serve its purpose very well. The handheld sensor (impeller) is lightweight and very low friction. Doesn’t take much air movement to spin it and register a flow rate. Often times I won’t even use the digital console when I’m just looking to see if I have some air flow or nothing. There’s plenty of modes and features in the digital console, but I only use the most basic ones. There’s plenty carrying and storage case is nice to have as I don’t use it much.

The BT-856A does measure air velocity and air volume. It is easy to use and provides the data I required. I needed additional sensors and the manufacturer quickly provided an Amazon link to order additional sensors. BTW, the additional sensors were very reasonably priced and arrived quickly.

This is a professional quality meter. For me, the primary purpose was for home HVAC testing/balancing. It performed its job well. Also helps to know temperature of air flowing. One downside was the instructions provided - not well written and not easy to find what you may want to do; even if all the functions are present.

This is a really useful tool, it works well. The only issue I have with it is the light does not stay on after you turn it on. I don't know why they did this that way, it's annoying as hell. They're led lights and won't drain much battery so I don't understand why they designed it to turn off so quickly.Outside of that it's a great product. (high impact plastic, don't drop it.)

I have used this HVAC monitoring meter for about a week and it seems well made, accurate and surely easy to read and use. I am impressed that the battery box is sealed from moisture by an O-Ring gasket and two small screws. Shows attention to detail by the designer and manufacture. A week of use is too early to say much more but I expect it to have a long and useful life in my tool kit.Alan

I just can't trust this meter. It's measurements are conflicting with my other equipment and I've determined it's definitely this meter. Half the time it's correct and the other half is off. I think I may have gotten a bad one. Will not buy again. Disappointed.Other than that it's very readable, easy to use, no issues with battery life, portability, or versatility.