Large silent fan for cupboard ventilation

octechno95

octechno95

octechno95

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I want to install a large PC case fan into a cupboard for ventilation. I want the fan to be as silent as possible so thinking that either a 200mm or 140mm size would be ideal. I know the fan will run at 12V but I want to run the fan off mains so is there a safe mains adapter that will allow the voltage to be stepped down safely so I can do this? The cupboad has a few passively cooled nework equipment so cool requirements are pretty low. It's already been working fine without ventilation for months so ventilation is just a small improvement.

The two that I were looking at were the Noctua 140mm or the Noctua 200mm I am slightly leaning towards the 200mm as it seems to run a lot quieter for comparable or better airflow.

Are there better options than these for around the same price? How can I connect these to mains?
 
Would probably go for 200mm fan
Shouldn't have to worry then
About something to control rpm as a 200mm
At full speed Shouldn't be loud

I would just use something like a cctv power supply
Usually they're 12v and up to 2 amps
You can buy female barrel jack connectors for them
So just cut the plug off the fan
Tape back the pwm wire if the fan has one
Then the +and- wires go in the holes on the female barrel jack
And screws hold the wires similar to in a standard plug

Edit
Would be 2.1 x 5.5mm female barrel jack connector
 
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octechno95 said:
Is it easy to power a PC case fan from USB? How would I do that for the Noctua 200mm? I need to mount the fan onto the inside wooden door. On the outside, I'll have a grilled vent cover.
Click to expand...
It would be a 5v fan
So lower rpm probably around 700-800 rpm
The noctua nf-a20 5v 200mm can run off a usb charger
Phone charger etc
Though its not a cheap fan around 30 quid

Edit
Basically the same fan you linked
But that's 12v
Need to search for same fan but 5v version

2nd edit
Ocuk don't seem to have 5v usb version
Amazon do
Though wont link it since ocuk do sell 12v version

​

 
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octechno95 said:
I want to install a large PC case fan into a cupboard for ventilation. I want the fan to be as silent as possible so thinking that either a 200mm or 140mm size would be ideal. I know the fan will run at 12V but I want to run the fan off mains so is there a safe mains adapter that will allow the voltage to be stepped down safely so I can do this? The cupboad has a few passively cooled nework equipment so cool requirements are pretty low. It's already been working fine without ventilation for months so ventilation is just a small improvement.

The two that I were looking at were the Noctua 140mm or the Noctua 200mm I am slightly leaning towards the 200mm as it seems to run a lot quieter for comparable or better airflow.

Are there better options than these for around the same price? How can I connect these to mains?
Click to expand...
What do you need to cool in this cupboard? How do you plan for air you want fan to push into cupboard to get out? I ask these questions because a fan can only much as air into a cupboard as is coming out. That's the simple physics of it. You also want cupboard to flow more air than fans on components in cupboard are using.
 
octechno95 said:
I want to install a large PC case fan into a cupboard for ventilation. I want the fan to be as silent as possible so thinking that either a 200mm or 140mm size would be ideal. I know the fan will run at 12V but I want to run the fan off mains so is there a safe mains adapter that will allow the voltage to be stepped down safely so I can do this? The cupboad has a few passively cooled nework equipment so cool requirements are pretty low. It's already been working fine without ventilation for months so ventilation is just a small improvement.

The two that I were looking at were the Noctua 140mm or the Noctua 200mm I am slightly leaning towards the 200mm as it seems to run a lot quieter for comparable or better airflow.

Are there better options than these for around the same price? How can I connect these to mains?
Click to expand...

I used a Noctua 200mm for the same thing. They are very quiet. You can also use a small PSU with a switchable voltage output to control the speed. When it comes to ultra low noise in situations like that, there are alternatives, but you aren't going yo get one much cheaper that is as silent. I know, I tried quite a few ended up back on Noctua.
 
Doyll has a fair point
Ideally you want 1 fan intaking air
And 1 fan exhausting
Though most cupboards aren't airtight
So if 1 fan pushes air in
Air is still going to escape around the door
But 2 fans should be better
 
You will probably need an intake and an exhaust fan for the airflow. Intake fan can be smaller
 
I've only got low powered fanless equipment. Cupboard has been fine without any fans for months so single fan feels like it will be enough of an improvement. Twin fan will be overkill. Cupboard isn't airtight so a single fan blowing out air will allow cooler air to be drawn in around the gaps of the cupboard.

Given a single fan, which direction should I mount it. Blow out air or pull in air?
 
octechno95 said:
I've only got low powered fanless equipment. Cupboard has been fine without any fans for months so single fan feels like it will be enough of an improvement. Twin fan will be overkill. Cupboard isn't airtight so a single fan blowing out air will allow cooler air to be drawn in around the gaps of the cupboard.

Given a single fan, which direction should I mount it. Blow out air or pull in air?
Click to expand...

Filter plus fan blowing in would help to keep the cupboard dust free, fan blowing out will suck dust in the cracks, etc.
 
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