Rad fans pushing or pulling

[Nightwings]

I'm wondering which is the better way to set up the rad fans. Pushing air into the rad or pulling air through the rad. Besides the dust issue accumulating on the rad when the fans are pushing into the rad what's the advantages of both setups?

 

[oneil]

The dust will accumulate on the side of the rad whether you're pushing or pulling, but in one of them you can just brush/vacuum it off. I'm sitting with a nice cake of dust between the fans and rad because I cant easily take them apart.

It shouldnt matter whether you're pushing or pulling air thru the fins, so long as you move the coolest air possible at the highest rate. So, depending on where you have your rad placed (off the back with a radbox or inside near some vents for example), try to blow the coolest air through your rad while trying to keep the warmer air out of your case.

 

[Waterboy]

I'm wondering which is the better way to set up the rad fans. Pushing air into the rad or pulling air through the rad. Besides the dust issue accumulating on the rad when the fans are pushing into the rad what's the advantages of both setups?

You'll get dust either way...advantage of pulling (this this to me, at least) is that dust will collect on the rad first and so the fan doesn't get as dirty. Also, it is easier to clean the dust off of the rad without having to remove the fans. I just use a vacuum host to suck the dust from the rad once a month or so. Quick and simple. I am not sure what advantages are as far as performance goes, although I think it is little to nothing.

 

[Nightwings]

Ok I think I'll just leave it with pushing. I have a pa120.2 mounted to the back of my cm stacker 832 and a pa120.3 mounted on the top. I think I'd be better off taking the air from the exterior than what comes in from the case side since there are exhaust ports on those sides. It's not a big deal to unscrew the shrouds and clean out any dust.

 

[Arcygenical]

I personally prefer pushing. Pulling is great too, provided the ONLY path for air to come through is the radiator fins... That requires a good seal between the fan and the radiator.

 

[BillParrish]

Pulling is the preferred method when correct mounting and a proper shroud is in place.


Pushing "throws" air at the rad in a directional pattern determined by the fan geometry of the housing blades and hub. For example there is a dead spot in the center of the fan due to the hub. Mounting the fans away from the rad can mitigate this somewhat but you still are "throwing" air, with fins/voids in the direct airstream getting more airflow than the edges of the rad.


However if installed correctly, fans pulling create an area of low pressure inside the shroud that sucks air more uniformly through the rad.

There are reams of posts on this and it was pretty much beat to death in the old forums at XS and Overclockers. However after the technical bit was hashed out (with much blood and gore) the final word is that the mounting and shroud have the greatest effect, pushing with a good shroud/mounting is better than a crappy pulling setup etc. etc. and sometimes you are limited in your mounting options. It was also determined that there is not a huge difference anyway with a good setup of either type. All things being equal, pull if you can.

 

[Waterboy]

Pulling is the preferred method when correct mounting and a proper shroud is in place.


Pushing "throws" air at the rad in a directional pattern determined by the fan geometry of the housing blades and hub. For example there is a dead spot in the center of the fan due to the hub. Mounting the fans away from the rad can mitigate this somewhat but you still are "throwing" air, with fins/voids in the direct airstream getting more airflow than the edges of the rad.


However if installed correctly, fans pulling create an area of low pressure inside the shroud that sucks air more uniformly through the rad.

There are reams of posts on this and it was pretty much beat to death in the old forums at XS and Overclockers. However after the technical bit was hashed out (with much blood and gore) the final word is that the mounting and shroud have the greatest effect, pushing with a good shroud/mounting is better than a crappy pulling setup etc. etc. and sometimes you are limited in your mounting options. It was also determined that there is not a huge difference anyway with a good setup of either type. All things being equal, pull if you can.

Thanks for the explanations....I've always used the pulled configuration due to my box limitations. I am redoing my box this week and had my box cutted so I can fit in a push/pull configuration. I will be using the Yates medium speed, which are ok by themself, but in a triple rad pushed/pulled configuration, they are loud. Is this due to turbulence within the rad and will this kill my fans?

 

[BillParrish]

Thanks for the explanations....I've always used the pulled configuration due to my box limitations. I am redoing my box this week and had my box cutted so I can fit in a push/pull configuration. I will be using the Yates medium speed, which are ok by themself, but in a triple rad pushed/pulled configuration, they are loud. Is this due to turbulence within the rad and will this kill my fans?

I honestly dont know, I dont think it would hurt the fans and (guessing) that the increase is due to air turbulence as you suggest because the way sound works is that 2 sources of equal noise level do not double the apparent loudness but you are adding 3 more noise sources so the increase could be significant /shrug. I would suggest you put a inexpensive Vantech fan mate controller (about $5) or controllers (one controller should be able to run 2 fans, maybe 3 check the rating of the controller and the rating of the fans) so you can dial in the amount of cooling you need and keep the noise down or consider rigging up a switch so you can flip all the fans to 7 volt operation when not gaming/encoding.