Airflow CFM Measured with a Hot Wire Anemometer! 

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One of the best demonstrations of how to measure CFM. I like where you take the measured air and compare it to the CfM formula is comparing the real and math worlds. Great video Craig and keep up the good work, 😀👍

Great job, you even showed how to do the math and check air flow by temp rise method! Who would dislike this video?

6:20 - It looks like you’ve practiced to near perfection on this process. Spot on 11s each traverse!

i always heard how hartd its to measure airflow at a job , this is an incredible tool ... thank you

What if I want to measure a specific duct going into a room? And what if it's flex duct? How do you measure that?

How would you do this if it was flexible duct? Can you drill holes in the flexible duct and plug them just like you did with the ducts in this video? Or would it be different?

Great video. Thank you for sharing . Could you do video for heat pump winter inspection ? how to know Heat pump is work good in winter?

How does this compare to a flow plate? Is it as accurate?

Thank you for the videos your a legend

Good demonstration.

excellent video partner thank you for sharing!!!!.

what's the formula for a gas furnace?

Do you have it on just fan or is the Ac running when you do this test?

Do have a video testing a gas furnace cfm? Nice seeing it being demonstrated.

Great video !!!! Question, Where do we measure cfm when working with flex duct? At the plenums?

it would be nice to see you include the units of measurement and how they add to or cancel each other out so you arrive at the value you are working out. I always found it very useful when writing exams to include all the units when working through the formulas. Maybe an advanced version of the video. Or possibly that is already addressed in your books? Other wise excellent presentation. I will recommend your channel to my peers and apprentices in the industry.

does this formula work for gas furnaces? also, how would this work if checking a/c airflow?

How about at your individual vents, equal them out?

How can you do in the round duct. Do we still need to make couple of holes??

When do you make the decision to drill into a customers duct without them getting upset about holes in there nice ductwork?

Grt video sir... Can you pls clear a doubt do we have to enter duct size to get directly reading in CFM !!!

I've yet to do this. Thanks for the info!

Great video like always. Have one question. How to messure CFM if unit is working only on cooling and no heat strips for amps reading since ams on blower are to low. Thanks

I thought we are checking heating the whole time until he said 400 cfm/ton of cooling at the end 😂

What's the difference in tools to measure CFM, on the Fieldpiece SDMN6 Manometer and the Fieldpiece STA2 Hot Wire Anemometer? A manometer measures Atmospheric Pressure and an Anemometer measures Wind Speed. Just a different way of calculating CFM ?? Also, if you had to pick 1, which one is a "more useful" tool ?

Could you, please, answer one fundamental question about Hot Wire Anemometer? There are 2 thermistors in the Anemometer probe. But only one of the thermistors (the upper one) is to be exposed to airflow.The other thermistor(the lower one) must be hidden away from the air flow and it senses only the ambient temperature. Why you put both thermistors into airflow? Do I understand everything right? Please, explain.

Where do you take the amp draw if you don’t have heat strips. ?

does the book have instructions for checking airflow/cfm like in this video?

How about doing a demonstration on a return system with a 2 foot return box and flex duct attached. My readings are way off! example 16x25 box. With 2-12 inch flex for 2.5 ton system with a 3 ton blower. My anometer reading 1600 cfm! How the hell does that add up!

How accurate is measuring the heat differential to this method?. I am sure this is the most accurite but i dont want to purchase this instrument. Enjoy your video's.

Question, isn’t this formula used to calculate system capacity. Checking the name plate (total btu) I’m confused q=1.08 x CDL x delta T I know you solved for Cfm but then where is Q left in this example ?

Nice... question though. I noticed from other videos you check this formula/cfm using electric heating. How would you check it with normal gas fired furnace? Is it explained in the book (which I ordered the other day)?

Where would you take the amp draw reading on a gas furnace ?

How far down in a return for a roof top unit should I place this probe?

Is there a service tech book for refrigeration

So Air handler amp draw at the heat strips. Where do you take reading on a gas furnace?

Thanks!!!!!!!!

None of these are helping me im trying to figout cfm for a window ac and a mini split

Those cuttings from the unibit....are being sucked into the electric motor! Nothing like a magnet below your cuttings.

His electric heater is 100% efficient. But A/C is even more.

Cfm..... not cfm’s! Otherwise great video

This seems like to much work for a little window to diagnose a system

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