Help: Adding a Fan to my Cabinet (1 Viewer)

[Andrea W]

I want to add a cooling fan to my enclosed cabinet that houses my bedroom HT equipment. It gets super hot in there. Anyway, I did do a search and found some posts, but I'm an idiot because I don't understand how to power the fan. From the searches, I decided that I want to get a Silencer 80mm Cooling Fan (Link Removed). This is a 12V DC fan. I want to plug the fan into one of the (AC) switched outlets on the back of my Yamaha receiver. What do I need to go in between the fan (which has one of those computer power pluggy things) and my receiver (which has a normal outlet plug)?
Also from my research searching the forums, I'm going to mount the fan at the bottom of the cabinet, where the 2 hottest pieces of equipment are (receiver and dvd/ld player), so that the fan is sucking/blowing the air out of the cabinet. Sound right?

 

[Chuck_C]

You could use a computer power supply. Do you have access to any junk computers? You could plug a good old power supply into a switched socket and the fan right into the 12v. output plug from the supply.

Personally, I would use a 120v fan. You could hook it up to a variable wall switch to control the fan speed and noise.

Seeing that heat rises, could you put your hottest pieces of equiptment near the top of the cabinent? Exhausting the hot air from the top would be more efficent.

 

[Terry Wysocki]

Forty years ago, I had some (then) very high end audio gear with Rotron Whisper Fans cooling the stack (see thread). They were about 90mm with

 

[Andrea W]

[deleted]

 

[Terry Wysocki]

I think I've found at least an interim solution to my fan problem. I wired two 12v fans to a small modular power supply such as is found on cordless phones and other small appliances. It only puts out

 

[Andrea W]

They do make Silencer PC power supplies that are supposed to be quiet. I used an old power supply I had on hand, although I might upgrade to a Silencer power supply. You are right, the power supply is louder than the Silencer fans (rated at 20 db) I installed (but not loud enough to be distracting or noticeable when the TV is on).
Here is a link to the quiet power supplies:
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The Silencer 270 Slim (AT power supply) is rated at 34 db. It's $89.
Here is some more info on quiet power supplies and fanless power supplies:
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I've been investigating fanless power supplies. Looks like TK Power (http://www.tkpower.com/) has one (distributed through Orion Industries) that is rated at 120 watts fanless. It's $135, though. Yowsers!

 

[Ken_Z]

I'm looking for a 110 fan to plug into the switched outlet on my receiver. Has anybody got one setup that way? Surely there is a fan for this purpose??

Thanks

 

[Roy Wallace]

Radio Shack has a great selection of 110V AC fans ranging from 20 to 105 CFM. I have used one in the past and it worked very well. It was fairly quiet too, which is key in a theater setting.

RW

 

[Andrea W]

Do you know the noise rating for the Radio Shack fans?

Also, I'm pretty much eletrically disinclined. I'm assuming the 120 V AC fans come with two wire leads for the connector. What do you do to get it connected to a 2 prong plug to plug into the switch outlet on the receiver?

 

[Roy Wallace]

I did not see any noise specs on www.radioshack.com but someone else may have a better idea.
The fan I used had two connectors on it that I soldered a length of lamp cord with a moulded plug in right on the end, and plugged it right into my receiver.
RW

 

[Andrea W]

Wanted to share my completed project:
The equipment in my bedroom home theater is housed in an enclosed cabinet. It gets really hot in there.
Here is what the bedroom equipment cabinet looks like. Click the images for larger pictures.
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So I decided to add some fans to the back of the cabinet to exhaust some of the heat. I got two (12V DC) http://www.pcpowercooling.com/products/alarmandaccesories/silencerfan/index.htm http://www.pcpowercooling.com/products/power_supplies/ultra_quiet/silencers/index_ultraquiet_at.htm
I cut two holes in the back of my cabinet. One at the bottom (the hottest equipment, which is the A/V receiver and DVD/LD player, is located at the bottom of the cabinet) and one at the top (since heat rises). I installed the fans so that they blow air out (exhaust). I plugged the fans into the power supply and plugged the power supply into one of the switched outlets on my A/V receiver; so when I turn on the receiver, the fans automatically come on.
Here is what the fans look like installed on the back of the cabinet. Click the images for larger pictures.
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What a difference these fans make! The fans are pretty quiet (noise rated at 20 dB), and the power supply is quiet too (noise rated at 34 dB). And now, after a few hours of my daughter watching videos or DVDs, when I open the cabinet, the equipment is cool. Much improved!

 

[Richard_s]

I general the larger the fan and the slower it runs the quieter it will be for the same CFM. Just my 2 cents...

 

[JohnRice]

Andrea,

I would say you did the right thing for your solution. You definitely should use DC fans, since AC fans placed that close to your equipment will almost certainly cause noise in the system. Your power supply is probably greater than you need, but that is no problem. Placing the fans at the top and bottom and opposite sides left to right is good.

I'll say it again, you really should only use DC fans for this use. Plus, if you do use an AC fan on a dimmer, you you ABSOLUTELY have to be sure the dimmer is made for a fan, not a standard bulb dimmer. Also, as you "dim" or slow down an AC fan, you will be even more likely to introduce audible noise in the system.

Terry,

You will have no problem running a 12v fan at 7.5v. The problem with the setup you described is that you are drawing too much current for the transformer, which is a overheating and fire hazard. You really need to supply the fans with about twice the current you are currently providing.

What I do is use a 3" or 4" 12v fan connected to a variable output transformer. You really don't need to use a big, hot, noisy power supply like a computer uses. You can get really cheap ones from Harbor Freight which work fine. Just make sure the power supply can supply at least as much current as the fans consume. I use variable output supplies because adjusting the output voltage controls the speed of the fan. It doesn't usually take much air movement to get the job done, so you don't need to runs the fans at full speed.