AV Cooling - Ideas please

[M@verick]

Hi All,

Just looking for some help with an idea for cooling for a completely closed (vented front door, using radiator screening) AV cupboard. Ill post up a build thread later for anyone interested in seeing pics of everything however my immediate problem is HEAT.

The way that the lounge is appointed, and discussions with the missus have dictated a "wires hidden", "boxes hidden" approach to the AV set up. This has meant the following gear is involved:

46 inch LCD TV, wall mounted
Monitor Audio RS6 Silver Front floor standers
Monitor Audio 8 inch in ceiling centre
Monitor Audio 6 inch in ceiling rears

In the "Cupboard" -
Miller and Kreisel 12 inch active Sub
Yamaha RVX 1600 (?) Amp
Denon (cant remember the model) DVD player
Sky HD
PS3
Nintendo Wii
Ipod Doc

All wires - Speaker face plate terminals are situated at the back of the cabinet in the base, as are Cat 5e and telephone.

The cabinet is corner mounted - the back is closed off by a wall as is the right hand side. The Cabinet is of wooden construction and around 8 feet tall, the base and cavity to the rear were packed full of sound deadening material to allow me to mount the sub in the base of this unit. The system sounds great and the set up works well, unfortunately though the AMP, DVD player and PS3 are getting far too hot - as would be expected in an enclosed design. The shelves within the unit are moveable and as such i can give each piece of equipment much more headroom - but I cannot increase the width, i.e. the amount of breathing space either side of each piece of equipment (around 20 mm each side). As such I am intending to add air cooling by placing three fans as intakes (sucking cold air from the outside room via the bottom of the cabinet) and venting this air up through the cabinet - I will ventilate each shelf internally and mount a fan in the middle of each shelf to push air upwards throughout the cabinet. Im also toying with venting an exhaust fan on the right hand side at the back of each component (i need to add a diagram to make this make sense dont i ?) exhausting back into the room. Finally at the top of the cabinet im thinking of adding two exhaust fans pushing air back out into the room.

The design as sketched out above would entail around 12 fans. I am thinking of using 120mm PC case fans - typically high CFM units but set to run at their slowest possible setting, so as to keep them as quiet as possible (im happy with a low level of noise - i know the cabinet will not be silent, this is a trade off for having the gear hidden). However I am confused as to how to achieve this - my plan was to buy the lowest rated PC PSU unit possible, and simply wire the fans to this (I have built many PC's and am handy with a soldering iron) however and apologies for my long winded way of getting to this question...

How do I achieve this ? - given there will be no motherboard present how do i get the fans to start up ?. Also I would have thought some form of fan controller will be necessary (i dont want to use those resistor cables as i would like some form of controllability), again how could i wire this up given that all the fan controllers I have seen require connection to a motherboard ?.

Answers on a postcard please.

R.

[phil_cardiff]

How do you know that they are getting too hot? Genuine question. I've got my ps3 placed directly on top of my sky box in a wooden cabinet with only the front open. My amp sits directly onto my cd player on the shelf below. Can I expect imminent bork?

[M@verick]

Generally av kit needs air circulation to cool. Most gear has passive cooling heat sinks which expect air flow or ambient air temp to take away the excess heat. In a closed cupboard this isn't possible and they simply cook. In my case I know it's getting too hot as:

PS3 cooling fan ramps up very quickly to the point that it sounds like a jet engine, around fifteen minutes into a film.

DVD player freezes after being used for a while -this tends to coincide with the amp heating up the underside of the shelf it's sitting on

The amp gets quite literately to hot to touch. You could cook on the thing.

All of the above are too hot ! -not sure this means imminent bork, most have auto shut downs etc but it's not good for your kit no -that said I don't know how hot yours is running it might not be as bad a problem as mine -the PS3 is a good indicator as you'll hear it's fan ramping up when it's getting hot

R.

[IforB]

I've been having similar issues.

I don't think you need quite as many fans as you are intending, what you need to to create air movement and exhaust it. If you have some vents on the bottom and between each shelf and the a fan or two at the top of the cabinet of sufficient power, then that should easily move enough air to bring the temperatures down
You don't need to force air in, just pull it out, outside air will rush in the cabinet to replace it.

You can also buy a cooling unit to sit on top of your kit that soaks the heat away and has internal fans to then direct it away, but I haven't used one and so have no idea if it's anything more than a gimmick.

[Crackie]

M@verick said:

Hi All,

Just looking for some help with an idea for cooling for a completely closed (vented front door, using radiator screening) AV cupboard. Ill post up a build thread later for anyone interested in seeing pics of everything however my immediate problem is HEAT.

How do I achieve this ? - given there will be no motherboard present how do i get the fans to start up ?. Also I would have thought some form of fan controller will be necessary (i dont want to use those resistor cables as i would like some form of controllability), again how could i wire this up given that all the fan controllers I have seen require connection to a motherboard ?.

Answers on a postcard please.

R.

Hi there ~ I'm not sure how much controllability you would like but a PSU like this one may do the job for you if using 12 of the fans below set on their 5V 'slowest' setting.

Live, Neutral and Earth in..... 0 & +5VDC out with an adjustment pot built in.
http://www.ebay.co.uk/itm/5V-5A-DC-Universal-Regul...

These people appear to have some of the quiter fans available but they're fairly costly ( for 12 ). http://www.quietpc.com/products/120mmfans/afdp-120...

[M@verick]

Crackie said:

Hi there ~ I'm not sure how much controllability you would like but a PSU like this one may do the job for you if using 12 of the fans below set on their 5V 'slowest' setting.

Live, Neutral and Earth in..... 0 & +5VDC out with an adjustment pot built in.
http://www.ebay.co.uk/itm/5V-5A-DC-Universal-Regul...

These people appear to have some of the quiter fans available but they're fairly costly ( for 12 ). http://www.quietpc.com/products/120mmfans/afdp-120...

Hi Crackie,

cheers for that,yes this is the sort of thing i was thinking of employing. I actually have two of those 120mm fans from quiet PC laying around the place as well as two of the thicker (34mm?) profile Sunon Denki fans from a previous installation so potentially i need to find another 8, or less if i can get away with it.

Just in terms of wiring that though.... given there would be no motherboard - how would one wire this ? - I am used to dealing with three pin connectors on fans, and molex connectors on PSU's. Im probably asking a daft question but what cables would i need to make up to make this work ?.

Many thanks,

R.

[Crackie]

M@verick said:

Just in terms of wiring that though.... given there would be no motherboard - how would one wire this ? - I am used to dealing with three pin connectors on fans, and molex connectors on PSU's. Im probably asking a daft question but what cables would i need to make up to make this work ?.

Many thanks,

R.

Hi M@verick ~ the link to the fan shows 3 connection options; using the white 5v wire results in the slowest fan speed. Each fan's white cable and 0v cable will need to be extended back to the 5v DC and 0v on the PSU, I can't make out the fan wire gauge from the link but it should be fairly straight forward to find inline crimps to use at the fan end. Something like this http://www.ebay.co.uk/itm/50x-Mixed-Insulated-Red-...

The current drawn by each fan is very small so light gauge mains flex will be fine http://www.ebay.co.uk/itm/White-2-Core-Flexible-Ma...

The PSU uses screw clamp terminals so this pattern of crimp will be fine; it should be possible to put multiple fans into each crimp http://www.ebay.co.uk/itm/10-x-4-AWG-Gauge-Gold-Cr...

Good luck.

[M@verick]

Crackie said:

Hi M@verick ~ the link to the fan shows 3 connection options; using the white 5v wire results in the slowest fan speed. Each fan's white cable and 0v cable will need to be extended back to the 5v DC and 0v on the PSU, I can't make out the fan wire gauge from the link but it should be fairly straight forward to find inline crimps to use at the fan end. Something like this http://www.ebay.co.uk/itm/50x-Mixed-Insulated-Red-...

The current drawn by each fan is very small so light gauge mains flex will be fine http://www.ebay.co.uk/itm/White-2-Core-Flexible-Ma...

The PSU uses screw clamp terminals so this pattern of crimp will be fine; it should be possible to put multiple fans into each crimp http://www.ebay.co.uk/itm/10-x-4-AWG-Gauge-Gold-Cr...

Good luck.

Ahh. That makes sense, I think I was getting confused by the fact that some of the fans I have have 3 wires, and some have 2. Much appreciated for the links - i will order these up and have a go at it. Once everything is sorted Ill post a build thread with some pics.

I owe you a beer, feel free to claim it if you are ever around Alton way

Many thanks,

R.

[Odie]

id attached a USB connector http://www.maplin.co.uk/usb-1.1-plugs-22681 to each of the fans ive done this before, then plug all the fans into a USB hub or 2.

[TonyRPH]

20mm either side of the kit sounds minimal at best, especially if it's a solid "wall".

Having spent many years fixing this sort of stuff (before getting into IT) I've seen what excess heat can do, and my advice is to try and get it running at the same temps. as you would expect it to be at in free air, or else you will have problems in the longer term.

Most (if not all) domestic kit is under specified in the heatsink department - often as little as 40% of what it should be - so the kit tends to run hot when used at high levels for extended periods anyway, even under favourable conditions.

I would suggest taking a 60mm hole cutter, and cutting several holes in each shelf, particularly to match vent holes on the amp (I realise this is very specific and will not be right for other amps).

For the amp, I would expect to provide a minimum of 160mm clearance to the top, and at least 40mm to the sides (although I realise you can't provide the side clearance) so more holes to the side would be beneficial, both in line with the amp and above it.

I would suggest two 100mm fans in each side, to extract the hot air, and try to draw as much cool air through the door as possible.

The same goes for the PS3 as I know how hot they can get.

A diagram of what you have would be useful to see how much space you really have.

I think that once you provide adequate ventilation for the amp, ps3 and sub, your DVD cooling will take care of itself.

I'm not sure you'll require anywhere near as many fans as you're suggesting.

It may be prudent to vent the sub woofer separately, i.e. don't put any holes in the shelf above it, just leave a decent sized void (about 200 - 300mm) above it and vent it to the side, with fans.

I suspect that on a hot summers day, your kit will fail...

Edited by TonyRPH on Tuesday 3rd April 10:48

Edited by TonyRPH on Tuesday 3rd April 10:49

[freecar]

http://www.tomshardware.co.uk/forum/244578-10-turn...

That'll make sure that the PSU will supply 12V without motherboard.

I think you'll struggle personally to get it sorted, if you can efficiently purge the heat from one area you'll have to carry if past another area (that you're also trying to cool) which will heat that area up.

Ideally I'd seperate each shelf and have an inlet fan bringing outside air over the unit and exhausting out the back, that way the purged heat wont be warming up another area, or run a duct up the back and exhaust each shelf into it.

[Crackie]

TonyRPH said:

try and get it running at the same temps as you would expect it to be at in free air.

TonyRPH said:

I would suggest cutting several holes in each shelf, particularly to match vent holes on the amp. I would expect to provide a minimum of 160mm clearance to the top, more holes to the side would be beneficial, both in line with the amp and above it.

I think that once you provide adequate ventilation for the amp, ps3 and sub, your DVD cooling will take care of itself.

TonyRPH said:

I'm not sure you'll require anywhere near as many fans as you're suggesting.

I suspect that on a hot summers day, your kit will fail...

I don't understand here; they appear to contradict each other.

[TonyRPH]

Crackie said:

TonyRPH said:

I'm not sure you'll require anywhere near as many fans as you're suggesting.

I suspect that on a hot summers day, your kit will fail...

I don't understand here; they appear to contradict each other.

I meant as things stand!

[Crackie]

Hi M@verick ~ I think your idea of 'forced convection' i.e. cool air sucked in low down and exhausted at the top of the cabinet will be fine if used with TonyRPH's plan for additional strategically placed holes in the amp and PS3 shelves. It may even be practical to duct the incoming air, using something like PVC plumbing pipework, and direct it at the front vents on the PS3 and underneath the heatsink(s) on the amp. Reducing the total number of fans whilst targeting the flow from the incoming ones directly at the heat sources is likely to be more efficient, and less costly, than using the original plan to use 12 fans.

[M@verick]

Cheers Tony/Crackie,

Have taken those thoughts on board, and I am going to do a little of both - i have ordered the 5V PSU and fans you linked to Crackie. Tony unfortunately i cannot access the right hand side of the cabinet as it is bolted to a corner wall - the right and back being against the wall and the front and left being open to the room.

Heres an image:


as you can see space is tight and heat was always going to be an issue. I am going to move the shelves up, and may lose the top one/two to make the cavities bigger. I will then use a hole saw to cut several holes (6?) of 3 inch diameter on both sides of the shelves, in the middle of the shelf ill cut a square hole (which can take a 120 mm fan) .I will then use the second to bottom chamber as an intake (2 or 3 120mm fans) and duct these to the vented shelves pushing air up.

in each of the Sub, Amp, and PS3 cavities Ill put an exhaust fan at the back of each unit on the left wall exhausting out sideways. Ill then add a fan to every other shelf (mounted horizontally in the middle of the shelf) blowing upwards. At the top of the unit (behind the plinth) ill add two 120mm fans exhausting heat out of the top.

Im hoping i can get some general upwards airflow (convection should help this ?) so that the whole stack takes in cold air at the bottom and exhausts hot at the top - additionally as mentioned there will be rear exhausts for the hottest components - pushing these out sideways into the room.

Im also changing the standard fan for an enhanced 19 blade one (apparently with better bearings etc) and replacing the thermal paste on the CPU and GPU for Artic Sliver MX2 in the PS3 - just to try to help with conducting away heat.

I think this is about the best chance I have got with the area and build i have.

Cheers for all the help guys,

R.

[Himself]

phil_cardiff said:

How do you know that they are getting too hot? Genuine question. I've got my ps3 placed directly on top of my sky box in a wooden cabinet with only the front open. My amp sits directly onto my cd player on the shelf below. Can I expect imminent bork?

If it's an Onkyo amp then it will take about two years for the heat to buggger up the HDMI board Don't assume that because the equipment works ok for a few weeks that it's not being damaged by overheating.

[Driller]

How hot is too hot? My node zero has no ventilation although is a fairly large space.

Thermometer reads up to about 26 degrees in summer.

ETA Forgot to say, no forced ventilation, there are in and out grills top and bottom.

Edited by Driller on Friday 6th April 06:45

[VEX]

I keep client sky boxes cool by sitting them on laptop coolers the extra air movement has keep one box alive in a cabinet for over 3 years with no issues at all.

A great fix for around £25.

V.