great video. lookig foward to the hot wire. Im thinking since all my working is a basement splits with actual ductwork I will be leaning towards the hotwire. I will see how accurate it is once you post the video
Thanks for the video, I wish Testo would have some of this information on their website I love the products. Will 70% free space work for my hot wire anemometer the 405i? And please do a video for the 405 I I would really appreciate it
The 405i can be used in this same manor but is better suited for in duct traverse rather than at the grilles. (round or square pipe) I will be making a 405i tutorial video in the coming weeks. The 70% free space is just for this specific grille. Each style of grille has a different % of free space. Thanks for watching.
HVAC in SC Ok,thank you!!! Cant wait for the 405i video i appreciate the help with these products . I just got the whole set last week and good info is hard to find
The settings icon in the bottom right only allows me to “edit view”, doesn’t give me the configuration tab. And the play button doesn’t appear in the bottom portion. Can anyone help me out
The most accurate way to determine a free area measuring airflow on the same type of grille by pitot tube traverse and comparing that to the a measurement without a free area factor. The reading that you get by an accurate measurement divided by the measurement obtained by the anemometer times by 100 will be the grille free area percentage. Otherwise some manufacturers might provided this data. Generally though free area for a louvred grille like the guy measured is around 75% and for eggcrate grille around 90%. When you measure the grille area don't include the frame around the grille or large spaces in between and you don't need to measure these areas with the anemometer. Measuring airflow with an anemometer is not the most accurate way of measuring airflow especially when the velocities being measured are less 1 m/s or 200 FPM.
@@Blakepopp I haven’t used that one for a while but I remember that the correction factor is only used when you are trying to measure air flow. The correction factor is the free area factor. If you change the mode you can just measure velocity and calculate flow manually which is what I preferred because in the flow measurement mode it doesn’t tell you velocity. I recorded my data in an spreadsheet which can add your free area factor into it and grille size. If you just want a rough reading and don’t care about velocity you can use the flow mode, put the right area in (just the open part of the grille- not the frame). The factors normally work out to be around 0.9 for a return grille and around 0.75 for a supply grille.
That's more like it SC. I don't think you will ever come across a grille with more than 80% and that is like those mobile home floor return ones that don't have louveres. I have the same anemometer too and it's scary how accurate it is. Now we can discuss why you have such low airflow though lol
great video. lookig foward to the hot wire. Im thinking since all my working is a basement splits with actual ductwork I will be leaning towards the hotwire. I will see how accurate it is once you post the video
Thanks for the video, I wish Testo would have some of this information on their website I love the products.
Will 70% free space work for my hot wire anemometer the 405i?
And please do a video for the 405 I I would really appreciate it
The 405i can be used in this same manor but is better suited for in duct traverse rather than at the grilles. (round or square pipe) I will be making a 405i tutorial video in the coming weeks.
The 70% free space is just for this specific grille. Each style of grille has a different % of free space.
Thanks for watching.
HVAC in SC
Ok,thank you!!! Cant wait for the 405i video i appreciate the help with these products . I just got the whole set last week and good info is hard to find
Also check out HVAC School and Trutech tools on RUclips for more Testo information.
@@HVACinSC: If i'm using hot-wire in a duct, is "FREE SPACE" applicable? Don't i just enter duct dimension and do the traverse? Thanks
Hello friend from Argentina. I have bought a testo 410i. I would like to consult, is it normal for the reel to make a little noise when turning?
How do you find the free area of a grill. so many different ones in the field.
The settings icon in the bottom right only allows me to “edit view”, doesn’t give me the configuration tab. And the play button doesn’t appear in the bottom portion. Can anyone help me out
What smart probe tools would you recommend in order to get the numbers for the infamous p.u.d. rebates.
how do you determine the free area of a return grill?
The most accurate way to determine a free area measuring airflow on the same type of grille by pitot tube traverse and comparing that to the a measurement without a free area factor. The reading that you get by an accurate measurement divided by the measurement obtained by the anemometer times by 100 will be the grille free area percentage. Otherwise some manufacturers might provided this data. Generally though free area for a louvred grille like the guy measured is around 75% and for eggcrate grille around 90%. When you measure the grille area don't include the frame around the grille or large spaces in between and you don't need to measure these areas with the anemometer. Measuring airflow with an anemometer is not the most accurate way of measuring airflow especially when the velocities being measured are less 1 m/s or 200 FPM.
@@alibabahck do you know anything about the correction factor on the 410i?
@@Blakepopp I haven’t used that one for a while but I remember that the correction factor is only used when you are trying to measure air flow. The correction factor is the free area factor. If you change the mode you can just measure velocity and calculate flow manually which is what I preferred because in the flow measurement mode it doesn’t tell you velocity. I recorded my data in an spreadsheet which can add your free area factor into it and grille size. If you just want a rough reading and don’t care about velocity you can use the flow mode, put the right area in (just the open part of the grille- not the frame). The factors normally work out to be around 0.9 for a return grille and around 0.75 for a supply grille.
That's more like it SC. I don't think you will ever come across a grille with more than 80% and that is like those mobile home floor return ones that don't have louveres. I have the same anemometer too and it's scary how accurate it is. Now we can discuss why you have such low airflow though lol
Joe Shearer lol! It's like the mechanic with the car leaking oil kinda deal.
HVAC in SC especially when it's the rear main seal !
Joe Shearer Ain't nobody got time fo that! lol
Is there a formula for free area ?
You still using this?
Hello dear, so with this instrument we can measure the direct CFM !!
Yes
How? That’s what I’m interested in
How did you arrve at the 70% free space figure ?
Video is old an inaccurate. 😞
@@HVACinSC is there a formula for figuring the free space based on outlet size ?