In fairness to all, we don't discuss pricing on the Wall. Thanks for your cooperation.
help with measuring airflow
I am having trouble measuring duct airflow, I took a ventilation course and it seemed so easy but in the field I have never been able to replicate the procedure done in the classroom.
For example, I am trying to read the airflow being exhausted by a kitchen range hood through a 4" duct, I have a Dwyer 0-1" water magnahelic & a pitot tube (series 160, the coaxial kind with high & low connections on the same unit) but the gauge barely flickers when the probe is inserted in the airstream. I ran the calculation based on what I think it says on the gauge (.02" water) and get a ridiculously low CFM number.