New Anemometer $16 for checking CFM and temp works good!

  • Active since 1995, Hearth.com is THE place on the internet for free information and advice about wood stoves, pellet stoves and other energy saving equipment.

    We strive to provide opinions, articles, discussions and history related to Hearth Products and in a more general sense, energy issues.

    We promote the EFFICIENT, RESPONSIBLE, CLEAN and SAFE use of all fuels, whether renewable or fossil.

Don2222

Minister of Fire
Hearth Supporter
Feb 1, 2010
9,192
Salem NH
Hello
This is cool!
https://www.amazon.com/gp/product/B072HN7RMY/?tag=hearthamazon-20
This is a very necessary tool for any forced hot air heating or cooling appliance!!

You can test all the heat levels on the front of the pellet stove!!!

So I just measured the diameter of the little fan blade opening on the meter as about 2.7 centimeters which makes the radius 1.3 centimeters so that would be about 0.013 meters.
Now the area is Pi x Radius Squared = 0.057 Meters Squared
So the CFM = Area in Meters Squared x feet per min,
So CFM for the Englander Blower I measured on the exhaust flange is:
CFM = 0.057 x 1855 = 105.7
I know the Englander blower specs are 85 CFM so I am close but I am not sure where it is measured and my approximation of the area of my meter may be off also but for $16 I am not complaining!!!

What do you guys think???

Any more info on this meter for better CFM calculation?

Pic 1 - floor register with Harman on low flame!
Pic 2 - brand new Englander 85 CFM Exhaust Blower on Venting flange for a baseline to compare an old or dirty stove!
Baseline Feet Per Minute measured here is approx 1855 ft/min
 

Attachments

  • [Hearth.com] New Anemometer $16 for checking CFM and temp works good!
    A4936B1A-D869-4AA7-9852-4AB29AA387B0.webp
    47.2 KB · Views: 135
  • [Hearth.com] New Anemometer $16 for checking CFM and temp works good!
    329FF240-1E86-4522-90AB-ACF1AD0D1BAA.webp
    48.4 KB · Views: 145
Last edited:
They are fun,I have several cheep ones like that,use them for wind measurements when shooting.As far as cfm,blower motor cfm is measured right at the motor assembly,usually within a test duct,the size of the outlet,or the size for the particular installation.Measuring at the stove outlet will be representative,as airflow goes through turns,bends.Also,reading higher is very possible,because if airflow duct/passageway is downsized,speed will rise.That is why ductwork is usually stepped down,the longer the run in a house.Hope this helps.
 
  • Like
Reactions: Don2222
Don't forget you also have to take the efficiency of the fab itself into account, that will account for some differences too. I used to work for an industrial fan company many many years ago, the testing involved in fan design is really interesting. Sometimes just having an idea of performance is satisfying -