Holmes On Homes; last night again Holmes & the H-VAC Guy both read their anemometers as showing CFM Volume when they were showing FPM Velocity. (Rerun?)
It was a floor diffuser, didn't get a good look at it but was either a 4X10 or 4X12.
Initially said it was delivering 410-cfm/which was FPM; Hart&Cooley show a 4X10 as .17-Ak Free-air-area, which is 81.6-CFM.
Final was stated as 671-cfm which was actually FPM; .17Ak * 671-FPM is 114-CFM.
A 4X12 yields .195-Ak * 480 is 93.6-CFM; 671-FPM * .195-Ak is 130.8-CFM.
Ak is free-air-area of the diffuser.
The FPM Velocity would be astronomical if that .195 or .17-Ak were flowing 671-CFM,
I wish they would get it right from here on... Please...