Push-Pull Fan Setup

So, I've had 2 Noctua Fans sitting around for a few months not getting used, and I decided to use them as push-pull on my H60i just for fun.

They are non-matching fans. One is the high static pressure P12 model: http://www.newegg.com/Product/Produ...004&cm_re=noctua_120mm-_-35-608-004-_-Product

The other is the older revision of the FLX model: http://www.newegg.com/Product/Produ...037&cm_re=noctua_120mm-_-35-608-037-_-Product

So my thought was to have the FLX Push, and the P12 Pull. My thinking is that the static pressure fan will pull more air through the fins, and potentially help the airflow of the FLX to flow through the fins a bit better. Is this accurate reasoning?

I recognize that these fans are probably far nicer than this cooler can utilize. But I still think it will be a fun little change to implement for my system, and I will know I'm getting the most I can out of this cooler.

Only one way to find out, try both configurations under load conditions and record the temperatures.
Also make note of ambient temperatures.

Yep what he said, finding optimums can take a lot of trial and error.

Push/pull setup can really make a significant difference if the original fan configuration is not pushing much air through the radiator, leaving a lot of undissipated heat on the radiator fins. If however, most of the heat is being moved away already you won't find much improvement. 0-2c improvement over stock has been my experience when trying push/pull on many different air and water coolers. What you don't want is employing a pull fan that doesn't move enough air to prevent actually creating an impediment to the flow of air from the push fan through the radiator. Most well-designed AIO water loops are probably not going to benefit much from adding a pull fan. The manufacturers have already figured out how much air flow the radiator needs to dissipate most of the heat produced in the wattage range most overclockers deal with. At some point you just reach an equilibrium between several thermodynamic factors that make more air flow not help much.

It's also true that the greater the differential between coolant temp and air temp the more a pull fan or even a more powerful push fan will help.

its not a matter of trial & error.. the highest SP fan goes Push... always

RnRollie said:

its not a matter of trial & error.. the highest SP fan goes Push... always

Click to expand...

Thank you for this. I figured there was a theoretical approach that should be applicable. I wasn't sure if the static pressure worked when pulling, or if it was only while pushing. I'll install the P12 as a push, and the FLX as a pull, and see how it works.

The static pressure can work either pushing or pulling. When pulling it's negative static pressure and some experimentation with it both ways still might be in order. In my limited experience with water cooling I have discovered there are more opinions and more anecdotally-based convictions than there are hard and fast solutions. System variables can make different solutions work or not work. For instance, a different radiator with different thickness and different fin density can change what works and what doesn't.

well.. its called static pressure, not static suction but yes.. a lot of variables can impact behaviour & results.

Now look at this example... its basically two fans bolted together, believe me when say that the high-SP is the "push" one... https://db.sanyodenki.co.jp/product_db_e/coolingfan/dcfan/dc_fan_detail.php?master_id=2606

Not quit sure if this thing would work well as a radiator fan... but the thing has some "throw" you can feel at quite a distance

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