[fst2011]

Hello,


I was not sure where to post this question, so if this is not the correct place, please point me in the right direction. Next, I will try and explain best I can but if it does not make any sense, just let me know.


Few years ago, I built a wall to hold the cable box, dvd, etc. and it also went just over the top of a huge 60inch Sony rear projector tv. Looking at the 1st pic...take away the 2x4's that are showing...and that big hole is where the tv went.


About 2 months ago, I got a new Panasonic 65inch GT 30 Plasma. Looking at 2nd pic, you can see 2 pockets or holes, this is for the 3D DVD player and Xbox. Also, look past the studs, and you should be able to see that there is room to stand behind the wall once it is finished.


Pic 3...shows placement of tv ( still needs paint)...also look to the right of tv and there is a space between the wall and window. This is how I will get behind wall.



Now for the question:



I want to know if it would cause damage to either the tv or components, if I have a fan blowing on them, from behind the wall?


Example....under the dvd player, there is venting cut into the metal, so it can keep cool. And on the backside of the Panasonic tv, there are 2 big spots where the metal has venting....(Plasma's get HOT).


My idea....was to cut a small square out of the sheetrock....for each spot that had venting. Meaning, the pocket I made for the dvd player...I would cut out a small area of sheetrock under the unit, where the venting is on player. Same goes for the Plasma.


Then I would put a small 12inch or so fan, behind the wall, place it where the air from fan would hit the holes I cut.


I know components get hot and the plasma gets very hot. I dont see how this idea could hurt anything but you guys here, would know better then me.



Please take the time and let me know what you think. I dont have the experience that most of you have. You might think of a flaw in this design...all advice is welcomed.





Thanks in advance,

Mike

 

[J_P_A]

I don't know the answer to your question, but just thinking out loud here. Does the TV have an internal fan? My concern would be if those vents are meant for hot air to exit, and you are trying to force air in. It might end up preventing the proper air flow.


I think you've got a good idea going, you just need to make sure your fan is blowing in the right direction.

 

[fst2011]

J.P.A.....thanks for taking out the time and trying to help me think this one thru. As for the fan built into the tv....yes it has two, one at each end. So, depending on what the rest of techs here say....I will either leave the sheetrock alone where the fan on the tv are.....or I will just make sure the cool air blowing on the tv, does not go near the holes for the built in tv fans.



If you or anyone else reading this has idea on if I should continue or etc please let me know. I'm going to wait it out a few days and give some time for other members to answer.




thanks again for the help


Mike

 

[jautor]

Assuming the TV is mounted on the wall using a standard wall-mount bracket, that's how every one is done, and no extra venting or fans are necessary... Meaning - they're designed to be placed like that.


Now, if you enclosed it or blocked airflow, that would be a different story.


But, did you provide any circulation holes for the components? If that's a xbox or playstation below, it'll want some air movement!


Jeff

 

[J_P_A]

I originally thought you had the TV recessed into the wall, but now that I look at your pictures again, it looks like you are just planning to hang it on the wall like normal. If that's the case, then I agree, no fan needed. The components underneath are a different story. They'll need some fresh air as mentioned above. I'd just figure out where the hot air is vented on each component and put a fan near that area to exhaust the hot air. it may not make a difference in the short term, but considering how small the openings appear, I think some ventilation will extend the life of your components in the long run.

 

[fst2011]

Thanks again all for taking time to share your advice. As for the tv mount... You both are correct, it is hanging on the front wall.


I understand that the tv was designed to be this way but I just wanted to add some extra cooling. Most people who hang their tv, do not have the option to have fan running behind it.


I know you both said tv does not need it, but if I did use fan, do you think it would cause damage and if yes... Why?


The components all have venting cut into the sheet rock shelf.... And the xbox, has extra venting...under it, right side and the back.




Thanks so much everyone,

Mike

 

[jautor]

Quote:

Originally Posted by fst2011 I know you both said tv does not need it, but if I did use fan, do you think it would cause damage and if yes... Why?

Probably not, but since it doesn't need it - why do you want to add the extra noise and power consumption to your system?

 

[fst2011]

Well the noise would be very little if at all...i have one of those whisper fans and its about 12 or so inches. As for the power consumption... You got me there, I guess it would but I just feel that the plasma get hot... And it would only help keep it cool.


Everyone goes thru all kinds of trouble (spending money) , adding lights or extra gadgets, etc....so what's a $20 buck fan...and a very little extra electric bill...if it will keep the $3000 dollar tv cool and possibly extend the life of the tv.



But... This is why I came here....i wanted to make sure it would not damage it. You guys know way more then me and thought it best to ask first.




Mike

 

[J_P_A]

Just make sure you have the fan either blowing on the air INLET or pulling air away from the EXHAUST. If you get it backwards, then you will likely shorten the life of the TV as this will reduce the airflow through the set. Otherwise it can't hurt anything.


Just as a side note, Dennis Erskine has posted many times that it's preferable to have your fans pulling as opposed to pushing in ductwork. I would think the same principles would apply here.

 

[fst2011]

J P A .... Thanks again for helping think this thru. As for the info on pulling the air out instead of pushing new air in.... How did he find this method to be better? Meaning, is there any data to back up his advice?


I hope that did not come off wrong, cause I truly mean no disrespect. It sounds like it makes some sense but was wondering, if he had tried both methods, and recorded some data.


Thanks again so much


Mike

 

[fst2011]

Hello again everyone,


Just wanted to check in and see if anyone knew of data to show that its better to pull the hot air from components or better to push cool air into components.




Thanks for all the help, this forum has been so great at helping. And the members here are extremely helpful.





Mike

 

[jautor]



Quote:
Originally Posted by fst2011 /forum/post/20892316


Just wanted to check in and see if anyone knew of data to show that its better to pull the hot air from components or better to push cool air into components.

It's just a basic fact. More efficient, works better. Look on any equipment you have (PC, etc.) - the fans are pulling air out of the equipment, not pushing air into it...


Jeff

 

[J_P_A]

I'm the wrong kind of engineer for this, but I think it has to do with the compressibility of the fluid. Fluids like water we would typically like to push, particularly if we are pumping the fluid a great distance vertically (obviously this is a generality, so there are countless cases where this is not true). But, because air is compressible, we are dealing with different fluid dynamics.

 

[scottsh]

Don't forget hot air rises. It is generally better to pull hot air if your fan is above as you are helping vent it away. If the fan is below it might be better to push IF you can assure yourself the air you push is the same or lower temp than the ambient inlet air. If not you would be hurting.

 

[J_P_A]

+1


Unless he's planning to run a duct from the fan to the inlet on the TV I think it would be tough to keep from pushing some of the hot air back into the TV.

 

[ponchochicken]

I am dealing with a 2 year old plasma TV that is now dead due to failing cards, and I believe it has everything to do with the fact that this model has no active cooling! It cooked itself to death! I'll post more on that later, but any type of wall or hole mount TV is going to face cooling issues. I disagree with the blanket statement that " sucking is better than blowing". There are many examples of a fan directly on a heatsink; blowing is MUCH better because you disturb more molecules. But as others have said - you really want to design your cooling so it compliments and doesn't hinder the manufacture's design. Most take a convection approach, where heat rises up and out. Blow into the bottom, or suck out the top. I am putting together a system that taps off the TV's USB port; when the TV is on the USB delivers 5v to a relay, which switches on a 12v power supply and spins up my 6 computer fans. Why do I have to do this, rather than Samsung???