fan sizes for canopy

[knoxtnreef]

hi all,

is there a standard for the fan measurements in a canopy? I do not have custom lighting (i have the outer orbit) but I'm getting a canopy and they can precut my holes if i just tell them what to do.

 

[AquaVolGP]

i know dr foster and smith has fans for sale in their mag and on their website...

 

[knoxtnreef]

from what i can see the standard appears to be either 3 inch or 4 inch...

 

[fishdoc11]

Here is a good idea of the various fan sizes available:
http://www.allelectronics.com/make-a-store/category/220/Fans/1.html
Measurements are listed next to the fan but IMO it's best to order the fans and measure to be sure. For instance I have 4.5" holes cut for the fans in my hood but they are listed as a 4.69" opening. You could always call or Email whoever you are getting them from and ask but they will likely just read the dimensions.
hth, Chris

 

[Runner]

4" is what I used for my old hood. The moved about 90 cfm of air each. The smaller they are, the faster then need to turn to get the same cfm -- which means more noise. Go with the 4" unless you have space constraints.