- #1
rah32d
- 1
- 0
I looked, but didn't see any post on this topic. This is in regards to the selection process for fans/blowers in ventilation systems, which I am still new to.
From AC/Hr and the room volume we know the required CFM we need to supply to the space, and we can determine the size of ducts and FPM while adhering to basic rules of thumb (i.e. inlet FPM ~ 500 ft/min). My problem arises when calculating the pressure loss/gain through the system. Determining the loss/gain for ducting and fitting is simple enough, but how do we determine the pressure gained from the fan/blower?
From what I've seen there are only vague graphs of pressure values in relation to air capacity, which seem unique to each fan. Is the only way to calculate the required pressure gain from the fan to back calculate after I've determined the loss from the supply ducting?
From AC/Hr and the room volume we know the required CFM we need to supply to the space, and we can determine the size of ducts and FPM while adhering to basic rules of thumb (i.e. inlet FPM ~ 500 ft/min). My problem arises when calculating the pressure loss/gain through the system. Determining the loss/gain for ducting and fitting is simple enough, but how do we determine the pressure gained from the fan/blower?
From what I've seen there are only vague graphs of pressure values in relation to air capacity, which seem unique to each fan. Is the only way to calculate the required pressure gain from the fan to back calculate after I've determined the loss from the supply ducting?