Which is 'better'?

[fazidk]

Hi guys..Kinda stupid question I think but just wondering which is better..to have d radiator fan behind Sucking air or in front blowing air?:wavey:

Thanx n rgrds

Fazid

 

[Waiora_ProTuner]

Good question here! Been waiting a long time for this kind of question..

its like my early days when i ask question why sports car RWD, and got answer because 'tolak' is better than 'tarik'..
then why car mostly FWD...because 'tarik' is more efficient...

will compile my 10cents answer on TS question later..

 

[leonl]

Hi guys..Kinda stupid question I think but just wondering which is better..to have d radiator fan behind Sucking air or in front blowing air?:wavey:

Thanx n rgrds

Fazid

I would think behind sucking air should work a little better, that is why most car has it set up that way from factory. If the fan is in the front, then first it would blocked most of the air and also the part when the motor is will have a "un-cooled" spot all the time.

 

[Waiora_ProTuner]

Its the same amount of flow...whether front or rear..

the difference is more on flow pattern...blowing will create turbulence air which need to be controlled or to be settled for constant flow...
while suction is laminar flow...but then, its not able create strong force towards an object (due to the fact that it is not a force actually but a by-product from blowing force)

also, blowing create positive pressure...although not so high, but the theory is when you're raising pressure, the temperature follows..

and the fan creates barrier between radiator and engine...dividing the air temperature difference between both...so the engine won't 'heat' the radiator...

 

[cvkit17]

1. Blowing or draw through, they both have pressure which is quite irrelevant if the fan is adjacent to the radiator. Forget about the amount of flow. Flow in = flow out if no blockage and the fan static is enough to overcome the static pressure (blockage).
2. Blowing might have one not so important disadvantage. The fan itself is driven by a motor and there are energy losses which transform into heat. If the cold air pass through the fan, it's temperature rises. But I don't think it is significant.
3. If the fan is in front of the radiator, it has to be rigid enough to withstand sands and stones.

 

[vr2turbo]

To me, it bores down to design. Mine the radiator fan sucks and the air con one blows. This is due to enough space for radiator fan inside engine compartment, and for air con fan blocked by exhaust header, so need to be install in front. For wira both fan sucks as far as I remember.....

 

[cheeks1313]

bro, when the car move, the cool air eventually blow in 'thru front of the radiator....so the fan suppose to be fit at the back of radiator to perform sucking task...what's the point of having it fit in front to perform blowing ???

 

[neohadri]

Radiator fan placed there to create pressure different so air can travel from high to low pressure, on most car the fan will push air out from engine bay thus creating low pressure.

If the fan blow air, it still can create pressure different, but not as efficient compared to fan that sucking air.

 

[ColdPlay]

To have the fan in front of the radiator blowing air is hopeless. You might as well get rid of the grill / air duct or whatever is it. Point is, The higher the car speed, the faster the air blow in and this cool down the radiator. Its only logical to have another fan behind sucking aka blowing air to the engine compartment to improves the air flow.

 

[mADmAN]

as mentioned... airflow is the same....but its better to put it in the back... coz when u move.. having the fan in front will impede the extra airflow going to the radiator.

ive also had a friend who used to have a double line number plate (which the 2nd line is blocking the airflow a lil bit) causing higher water temps... changed to single line and all good.

 

[fazidk]

Gr8 info guys thanx..tho some lingo I x quite understand hehehe but I get d point (I think)...anyway reason me starting this discussion coz there are (conflicting??) regards to d position of d fan..some say behind is better some says front..correct me if I'm wrong but there are ones that come front as OE (rite???)..anyway mine is located behind n planning to 'mod' d aircon fan (which is in front) to run together wiz d radiator fan like bro vr2turbo mentioned n has done..I guess there's x side effects then?

 

[neohadri]

Gr8 info guys thanx..tho some lingo I x quite understand hehehe but I get d point (I think)...anyway reason me starting this discussion coz there are (conflicting??) regards to d position of d fan..some say behind is better some says front..correct me if I'm wrong but there are ones that come front as OE (rite???)..anyway mine is located behind n planning to 'mod' d aircon fan (which is in front) to run together wiz d radiator fan like bro vr2turbo mentioned n has done..I guess there's x side effects then?

there's a good reason why ur car's aircond fan is in front of the condenser from the factory, relocating it might not be a good idea,

unless u relocate the condenser to another area or u made some mod to ur car front grill, i think u should just leave it that way

remember, for radiator/condenser to work properly, they need pressure different between front & rear, otherwise air will not move thru the radiator/condenser

 

[TitanRev]

I think the difference is not much being it pulling or pushing. Engine space would be the main concern though is not enough space inside the engine bay you can opt to put in the front. My 206 is having it's fan places infront of the rad but it's a 2 speed electric fan.

Just a note though, if you going to install new rad fan. After you decided the fitting position make sure to test the fan before buying because the direction of the fan blade will determine the direction of the air flow.

 

[wsukun]

I think the difference is not much being it pulling or pushing. Engine space would be the main concern though is not enough space inside the engine bay you can opt to put in the front. My 206 is having it's fan places infront of the rad but it's a 2 speed electric fan.

Just a note though, if you going to install new rad fan. After you decided the fitting position make sure to test the fan before buying because the direction of the fan blade will determine the direction of the air flow.

Titanrev, the terminal wire can we swap to counter the original rotation right? but yeah, why the hassle. better check before buying.

 

[vr2turbo]

I think the difference is not much being it pulling or pushing. Engine space would be the main concern though is not enough space inside the engine bay you can opt to put in the front. My 206 is having it's fan places infront of the rad but it's a 2 speed electric fan.

Just a note though, if you going to install new rad fan. After you decided the fitting position make sure to test the fan before buying because the direction of the fan blade will determine the direction of the air flow.

Yup, my friend Citroen ZX have both fans in front but 2 speed.....

 

[fazidk]

there's a good reason why ur car's aircond fan is in front of the condenser from the factory, relocating it might not be a good idea,

unless u relocate the condenser to another area or u made some mod to ur car front grill, i think u should just leave it that way

remember, for radiator/condenser to work properly, they need pressure different between front & rear, otherwise air will not move thru the radiator/condenser

Oh I'm x worried coz I x have aircon..been faulty s long s can remember :)..repair after repair after repair but stil x permanent..x sure y tho..

 

[TitanRev]

Titanrev, the terminal wire can we swap to counter the original rotation right? but yeah, why the hassle. better check before buying.

Yes we can but if it's a 2 speed fan it might not turn. Single speed DC motor we can swap the terminal.