Axiom Home Page Forums General Discussion Home Theater Help with ventilation for electronics

Hello everyone.

I need some help with the ventilation of this Entertainment Center Console, (click the image on the right). The part I am speaking of has the glass doors on either side and three drawers in the center. The inner dimensions of each side to be ventilated are 19"W x 23.5"D x 21"H. There is a glass shelf that divides the upper and lower half with a 1/4" gap on all sides. The rear is covered with pressboard and has openings for cabling.

While I am aware that this isn't the best option for storing electronics, this passed the WAF. I currently open the glass door when viewing TV through my Comcast DVR since the DVR heats up like an oven. I will be adding an HTPC soon and will want to keep it cool.

I have found something that might work, but would like to get your opinions/ recommendations. I found this Fan setup on E***. Would putting a setup like this in the upper section of the rear panel remove the heat that rises? How about the same setup to draw in cool air?

Thanks in advance for your help and responses,
Shaun

Hi Shaun,

I would guess that a fan(s) are definitely the answer to your dilemma. There have been some threads here on the forum concerning this issue. You might do a "fan" search for suggestions. You definitely want to be sure to get a fan(s) that is quiet, and efficient. Maybe some of our computer experts, who know about these types of fans, can offer a critique of the fans you're looking at, and/or offer other suggestions.

those stupid DVR boxes do get pretty hot. I figure when i get mine, if i fry it because of not enough ventilation or whatever then oh well, i'll just have the cable company give me another one

I have DirecTv's HD DVR and have never noticed it to even get warm, the unit has a fan on the back but I don't recall ever hearing it, and per instructions my DVR is on at all times.

Shaun, the only thing I would be concerned with is the amp draw of the fans. You need to find that out.

The 24 volt thermostat shown has a max current rating of only 2amps. If the fans are close or slightly over, you will be burning through thermostats like candy. Idealy, he should have installed a small glass fuse in-line.

There is no mention of warranty that I could find in the add. (Honestly, I really didn't look that close)

You might want to look at the Middle Atlantic Ultra Quiet Fan Panels, We use them for some of our projects at work, theyre nice. but expensive.

Middle Atlantic Fans

How expensive are we talking here?

a few hundred $$$ :O

Oh, and Jack is right - there was no mention of the Db rating in that add. (But the guy's feedback does indicate that his buyers think they're quiet)

Haoleb, those are nice looking fan panels but a little pricey.

real80sman, so far his ratings are good, but you know how that works. No follow ups to say it broke in three days.

I was just talking to my brother-in-law the "Electrical Engineer" and he suggested the pre-fab way too. I think he meant he didn't want to volunteer to build them for me. His X-mas gift just got downgraded to a Dollar Store gift card valued at $1!

I found another site with Pre-Fab units. Sadly, none have a thermostat installed. It would work for my Yami V2600, but not for the HTPC. The size is right there. I can fit something up to 19" total, with the fan width to around 17".

Here is where we installed the console. I almost need to grease the sides of the console to squeeze it into the alcove. It's six inches from the rear wall, so there's room to move air back there.


Please forgive the flash. The Yami is unseen on the left under the DVR. The HTPC will go on the right under the DVD player.

So I'll re-phrase one of my questions. Would you (1) Go passive for a cool air intake low on the back and powered up high to remove the heat? OR (2) Powered fans for the intake and exaust?
Keep the ideas coming!

Shaun

Shawn, I wouldn't spend my money on those racks. You can easily do it yourself. Those prices are ridiculous for fans. I think they are simply targeting a niche of home theater enthusiasts and they can jack up the prices because they are custom for home theater. I was really surprised at how hiiiigh those prices were.

All you need to do is buy a few Silent Computer Fans 120mm Cooler Master Fan - $13 - 11.27 CFM - 13 dBA

Vantec Stealth Fan - $18 - 53 CFM - 28 dBA


If you want to make it a nice system, cut some holes in your entertainment system to put these fans in. I don't know if you have any gaps, for airflow or not, but be sure you have a way for air to get in if your fans are blowing out.

I would say you need about 30 CFM (cubic feet per minute) of air moving through your "areas" for the best heat dissapation. If you aren't paranoid about 28 dBA (also consider these fans are going to probably be inside your entertainment center thus cutting down on noise) I'd get the vantec ones. One on each side would easily ventalate your system silently. Research some computer supply stores and look for good fans. Another good place to check is www.svc.com

Alright, so how do you power these things? The amp draw from these fans are about .05 mA (miliamps) when they are running, .2 mA when they are starting up. They run off of 12 Volts. Sometimes the amperage ratings for each fan is listed on the website.

Go buy an AC adapter. This one has 1000mA of capacity, way more than you will ever need.

All you need to do now is get some small guage black/red speaker wire (24 guage or something) and start wiring up your fans. Once they are all wired up, cut off the plug to the AC adapter and split the wires. Test connecting one wire to the red and one to the black to see wich one is positive/negative. You will be able to tell which way the fans are supposed to be blowing by the arrow that is imprinted on the side of them.

Now, plug it in and you have a constant airflow system for under $50 with plenty of airflow and a custom installation to cool what needs to be cooled the most. It doesn't need a temperature probe because you can just leave it on all the time.

If you really wanted the power to turn on/off fans you can get a computer fan controller and hook it up that way. There are a plethora of controllers, some even have temperature monitors but mind you they are designed for computers. Here is a link of a large selection. http://www.frozencpu.com/cat/l2/g36/c17/list/p1/Fans-Fan_Controllers.html

Hope that helps in some way. If you have any questions, just post them here. I winced at the prices because something like this is very easy to make if you put your head to it.

Quote:

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The amp draw from these fans are about .05 mA (miliamps) when they are running, .2 mA when they are starting up.

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WOW! Thanks Dan, I had no idea those things drew so little juice.

Shaun, no worries with a standard (or even digital) heat/cool thermostat, then.

Yea, those were the close spec's of the silent (coolermaster) fan which runs at a low RPM so it uses very little juice.

Most fans are somewhere in the .05 mA - .5 mA range depending on their RPM speed and size. Most are around .2 mA

Very good info Dan.

I would think you only need to draw the hot air out of the cabinet. With an intake opening on the other side so that cool air can be drawn thru the entire cabinet. No need for fans on both ends.

Thank you Dan!

I needed a little nudge to try this on my own. I considered the DIY route, but just couldn't figure out how to convert the AC power to the fans without over-juicing them.

I'll try the passive route for the intake. The holes for the cabling should be large enough for supply.

Thank you all for your suggestions and help,

Shaun

BTW, just so you know... the radio shack AC fans (at least the 4" ones) are far too loud.

I have a fan I bought from Radio Shack and it just sits on top of my receiver out in the open. Although I can hear it when my stereo sound is low, it is very quiet. I can't imagine even hearing if it is the back of your cabinet. Check out the link in my signature to see.

Thanks for the response shag.

I was having the most trouble with the conversion from 3 or 4 pin to ? for powering the fan. Dan had a great idea, thank you for that Dan!:

Quote:

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Alright, so how do you power these things? The amp draw from these fans are about .05 mA (miliamps) when they are running, .2 mA when they are starting up. They run off of 12 Volts. Sometimes the amperage ratings for each fan is listed on the website.

Go buy an AC adapter. This one has 1000mA of capacity, way more than you will ever need.

All you need to do now is get some small guage black/red speaker wire (24 guage or something) and start wiring up your fans. Once they are all wired up, cut off the plug to the AC adapter and split the wires. Test connecting one wire to the red and one to the black to see wich one is positive/negative. You will be able to tell which way the fans are supposed to be blowing by the arrow that is imprinted on the side of them.

I winced at the prices because something like this is very easy to make if you put your head to it.

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Sadly Dan I'm not that great at wiring, so all I heard was the wah wah wah wah sound from Charlie Brown's teacher.

Since this post, I have seen all kinds of USB powered stuff. This Thermaltake Mobile Fan II External USB Cooling Fan interests me most since it has a cord/cable capable of powering the fan externally, though I wouldn't need the retractable feature, without having to work that hard at it.

I am thinking about using an 80mm fan to duct cool air in from the rear towards the front of the enclosure / HTPC and a 120mm fan venting out of the upper rear. It would seem to be easier to duct air in rather than having to attach the ducting to the rear of the case for exaust since the case will need to be pulled out from time to time.

Keep em coming!

ShaunB

If you have a 3 pin or 4 pin connector on a fan you just snip it off.

Trust me, all you need to do is make about 3 foot extensions to the BLACK and RED wires of each of the wires and connect them in one spot. Shouldn't be too hard. Heck, I could do it for you and mail it to you if you really wanted. USB stuff might work if you wanted to do that as well, more expensive, however.

A lot.

A 1000mA supply should be able to run 3 or 4 of those fans you mentioned before (the 80 and 120mm). Those use 250mA or almost 300mA. You just divide the current the fan uses into the supply total.

There are other fans that will do better, the 2 that Dan mentioned earlier are much lower in power consumption. Although they note 2.52 Watts to start up, which is about 210mA. So I still wouldn't try more than 5. You don't want the supply to get too hot.

It's all a trade off between this and the air flow (CFM), and of course noise.

Yea, I made a typo. Fans draw .05A not .05mA. Hehe.

Here's another source for fans:
http://www.nexfan.com/casefans.html

I used an old laptop power supply; we have tons of them here at work. Just spliced into the DC side. With most of these fans, you can also supply them with lower voltage, just make sure your power supply has enough current. They will turn slower, but still move air. I'll plug it into my Onkyo's (A/V receiver) switched AC outlet & be done with it. Onkyos tend to run hot and I don't have much headroom above the receiver.