Where can I find a small exhaust fan with a standard wall (AC) plug? (1 Viewer)

[John Pine]

I need it for a large enclosed TV stand, which now houses my receiver and DVD player. I want to install a small quiet (3-4") exhaust fan to keep my receiver cool. But I need to be able to plug it into a standard(AC)wall outlet. Radio Shack has some fans (273-241 & 273-242)but they don't appear to have a standard AC plug. Any suggestions?

 

[Shane Morales]

You need an AC power adapter.

My suggestion for your TV stand:

First, don't use those Radio Shack fans - they're way too small and will make a whining noise that will drive you nuts. You need at least 92mm or 120mm fans.

And use more than one fan - 2 or 3 - in parallel, side by side. This will allow you to use quieter (slower) fans and move more air. Get the some Panaflo 92mm fans (and fan tails) and connect them to the AC power adapter. You could even make a fan bus or rheobus to manage the fans speeds.

Try newegg.com for a bunch o' fans

This sounds like a fun mini-project! I wanna play

 

[John Pine]

Shane: Thanks for the links! The cavity is a small (one shelf) area, only large enough to hold my Yamaha receiver(shelf) and DVD player on bottom. Do you really think I would need more than one fan? I thought one fan, mounted in the center, flush with the top of the cavity would be enough.

 

[Shane Morales]

It's not so much a question of how many fans, but how much air you need to move to get adequate cooling. One fan can move the same amount of air as two fans, but it has to spin a lot faster than the two fans and will therefore be alot noisier. If you can manage it I suggest two fans, but if you only want one then get a 120mm fan. A bigger fan moves more air at slower speeds.

I'm having a bit of trouble envisioning your shelf setup, but ideally you'd put the fans on top in blow hole fashion - the whole heat rises thing. Next choice would be the back.

And you want the fans blowing away from the gear, not towards it. The idea is to suck cool air over the goods and exhaust the hot air out the top or back.

The thing you have to watch for, tho, is dust. The more air you move the more dust is going to be a prob.

 

[John Pine]

Blow hole option is out because TV sits on top of TV stand. Fans exhausting out the back against the wall will be only option. Point taken on getting large slow/quiet fans!
Thanks!

 

[wil_chan]

hey guys couple of months ago i encountered the same problem but my TV stand wasnt that SMALL compare to his, anyways this is what my solution was i bought me the FAN same one that shane posted and instead of buying an AC ADAPTER i bought me a USB CABLE instead and plugged it to my PLAY STATION2 since it has a USB CONNECTOR, u just kindda have to MODIFY the USB cable so u can connect the POSITIVE and NEGATIVE of the WIRE from the FAN if u . sorry i dont have the diagram too busy with work and i dont take compliments well some people mite think it's a DUMB solution but hey i finnaly got that USB PORT from my playstation USEFULL. hehehe if u ahve any more question about this just pls ask i'll be glad to help since i got so many good advice from this WEBSITE

 

[Bob McElfresh]

They also make muffin fans with small filters that snap over the fan. With these you can blow air INTO the cabinent and the filter will take care of a bunch of the dust.

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You can also get 12 volt fans and use a Radio Shack Battery Eliminator to cut the voltage to 10/9/8 volts to slow them down to make them quieter.

 

[Darren{Moo}]

Middle Atlantic Products makes a line of small fans designed to be installed in rack enclosures that are powered via a wall plug. They might be adaptable to your use.

 

[Andrew Tompson]

I had the same problem with my Sony DVD player getting too hot. I looked around and didn't find what I wanted, so I built it.

I got a standard computer case fan (70mm) and a 12V AC adapter. The fan was too noisy for my tastes. What you need to do is get a 50-Ohm variable resister (or potentiometer) and put it in-line with the fan. Then you can adjust the speed of the fan to a noise level you can live with.

It worked great for me. I couldn't find a 50ohm pot with an off switch so I added a toggle switch too so I could turn it off. Then I mounted the fan and switch on the back of my cabinet.

Hope that helped.

By the way - 50 Ohms is hard to find. Mostly you'll see 50k Ohm. That's 50,000 Ohm and it's too much resistance for this purpose.

 

[Glenn Overholt]

Because the fan was too noisy at 12 vdc, I got a Radio Shack AC/DC adapter, set it on 9 volts, and plugged it in to the socket on the back of my receiver.

Glenn

 

[Ted Lee]

silly question from ted time.

let's assume the cabinet is relatively airtight (with closed front doors, etc.)

if you mount the fan so it blows *out*, won't that cause some sort of negative pressure in the space?

i always wondered about that...

 

[Shane Morales]

Yeah, the negative pressure in the space makes nice cold air from the outside come in anyway it can. That's what you're looking for.

 

[MikeWh]

Shane-- I'm a little confused. I see it the completely opposite way:

I think ideally, you really don't want it super airtight. Too airtight, and the fan will just create an eddy and the motor will eventually burn up. More pressure on the fan, the louder it will become, as well.

Ideally, you want an (almost) equal amount of air coming in as is going out, with the intake being directed over the hottest parts of the components. In a "mostly airtight" cabinet, I think you'd create little streams of high velocity air (making up for the low volume), running straight from these "leaking spots" to the fan. If your components aren't in the path of these streams, then you are pretty much defeating the purpose of the fan.

The best design would actually have an intake hose of some sort coming in from a cooler location (like near the floor) and pointed right near the hot components. Venting (the fan) would be best located at the top of the cabinet, and hotter components would be stacked higher. I believe I've seen some cabinet makers actually using an intake system like this, down in the toe-kick. Maybe it would be even better, placing the intake about a foot high off the floor, so you don't have so much floor dirt & dust to filter.

Thoughts?