Do duct reducers hurt fans?

I bought a used Phresh Hyper Fan Stealth from an online hydro store for £170. I ordered the 8 inch but they sent me the 10 inch version. Bonus right? Thats a £450 fan! The only issue is my duct socks on the tent I have bought and my carbon filter are both 8 inch.

If I use a duct reducer and run the fan at 50% will this cause reduced life expectancy of the fan. I'm using it to cool 2 x 400w hps in a 80mm x 160mm x 180mm tent and don't want to have my fan crap out on me mid grow.

Any advice would be appreciated.

Thanks,

9fingers.

Whats that like 500cfm at 50%? Might get a little loud on an 8" duct but shouldn't be too bad if you keep the run short.

dont run the fan on full blast if you reduce it.. i do duct work at a different static pressure but for us an 8" is half the cfm of a 10" at .1 static

your fan is different but id only run at 50% or less to lengthen the run time of the fan

in short your fan will be damaged if you reduce the inlet and outlet, if you run it on a high fan speed.

i would just do your original plan and then dial it until it sounds right

Thanks dudes, I will start at 30% and work up from there making sure i dont take it above 50%. Concerned about the noise though, thats why I went for this brand! I really don't want a jet engine effect. The other alternative would be to just do reducers to get me through the sock. So buy a 10" Carbon Filter, 10-inch duct, reduce to 8 inches through the sock, then back up to 10" to the fan. The duct run shouldn't be more than 5 meters (16 ft) from the filter to extract point.

**Edit, the fan will be outside the tent drawing air from carbon filter in tent.

Small fan big duct = Jet engine effect (100-300hz) like a whine

Big fan small duct = helicopter effect. (20-100hz)

The sound can change slightly depending on pressure and tube length