Part-Time TEC.....?

[Naja002]

Hey Everybody,

I've been lurking around this forum for quite a while now. I move on and always wind up coming back! I would really like to play with 1 or more TECs, but there's one thing I'm missing: Can I install a TEC block, etc and just use it part-time. In other words, turn it on when I want to, but leave it off otherwise.

I WC, so that's not an issue. But will the tec and block transfer the heat properly if the TEC is off? I think: No But I'm really not sure....

Any thoughts?

[littleowl]

you can do that if you set it up as a chiller but to put it direct die you cant because it becomes an insulator.

[repsol_23]

you can do that if you set it up as a chiller but to put it direct die you cant because it becomes an insulator.

Just out of curiousity, how long would you say it would take for a chip to burn out from overheating?

I only mention this because I finally got all my stuff in yesterday and tore my cpu apart last night. While putting it back together and getting it running (kinds half ass together with wires all over) I inadvertently forgot to turn on my meanwell that runs the tec to my 3870 card. I was running for a good 5 - 10 minutes easily and maybe more before I realized it. My card wasn't overclocked, as I was only running orthos to see my cpu temps with my new 340 tec, but my card temps never got above 46C! I honestly thought that a mistake like this would be catastrophic within minutes if that long. Maybe I was just fortunate and caught it in time but I really don't wanna find out how long would be too long!

[littleowl]

I killed a 3200+ amd and it only took me about 20min.
To answer your question it really all depends on the size and thickness of your cold plat as well as the heat output of your heat source. (example: CPU, GPU, North)

Thats a good question for jimbo because he is very good at the math. just need to tell him all the sizes of everything and what you want to know and he should be able to figure it out. It would take me a couple hrs to get you the right #'s

[[XC] Hicks121]

Hey Everybody,

I've been lurking around this forum for quite a while now. I move on and always wind up coming back! I would really like to play with 1 or more TECs, but there's one thing I'm missing: Can I install a TEC block, etc and just use it part-time. In other words, turn it on when I want to, but leave it off otherwise.

I WC, so that's not an issue. But will the tec and block transfer the heat properly if the TEC is off? I think: No But I'm really not sure....

Any thoughts?

Oh no Naja!!! Dont break any of the crunchers man!!

[repsol_23]

I killed a 3200+ amd and it only took me about 20min.
To answer your question it really all depends on the size and thickness of your cold plat as well as the heat output of your heat source. (example: CPU, GPU, North)

Thats a good question for jimbo because he is very good at the math. just need to tell him all the sizes of everything and what you want to know and he should be able to figure it out. It would take me a couple hrs to get you the right #'s

Not too necessary for exact numbers now that I know it isn't someting that will happen immediately!! I actually use the DangerDen TEC block for the Socket 478 mobo on my 775, which is why my 340 TEC runs quite warm (I think). I just gotta make sure not to work on my stuff really late/early in the morning. I was up til almost 4 this morning trying to finish what I had started just to try out my new pelt. Almost cost me a huge lesson!!!

[Naja002]

you can do that if you set it up as a chiller but to put it direct die you cant because it becomes an insulator.

Cool, that's half of what I was thinking--the ceramic would not transfer the heat well...ie, insulator.

Oh no Naja!!! Dont break any of the crunchers man!!

Maaaaannnn, if I don't tear some stuff up--Ima run outta reasons to buy more stuff! I'm waitin' on the light bill now.....don't think I'm gunna get a shock, but I got my metal shoe plates and hat on! I'm ready!

[Vinas]

Getting back to the non-hijacked OP...

I think you could use a TEC part time, but you need to be creative! It wouldn't be cost effective but for sure a fun project! Here's what I'm thinking:

[Naja002]

Cool idea, but for me personally its more involved then I want to get atm. It seems though that the top water block would need to be shutdown/turned off when using the TECs though....Otherwise it would be adding heat back into the block and/or drawing out the "cold".

Not sure how the copper thickness would play out when just using the water block.......

Any thoughts?

[littleowl]

Getting back to the non-hijacked OP...

I think you could use a TEC part time, but you need to be creative! It wouldn't be cost effective but for sure a fun project! Here's what I'm thinking:

I had that idea one time also but it will not work because the copper plate would have to be at as big as the tec and most of the tecs we use are 40mm to 50mm. The copper wouldn't get the eat to the tec for it to be cooled down.

[Uncle Jimbo]

Hey Everybody,

I've been lurking around this forum for quite a while now. I move on and always wind up coming back! I would really like to play with 1 or more TECs, but there's one thing I'm missing: Can I install a TEC block, etc and just use it part-time. In other words, turn it on when I want to, but leave it off otherwise.

I WC, so that's not an issue. But will the tec and block transfer the heat properly if the TEC is off? I think: No But I'm really not sure....

Any thoughts?

TECs are good insulators so you can't turn it 'OFF' - but there is another way to get a similar result.

TECs transfer the most power at zero temp differential. Let's say you want to cool a 100W heat source and are using the ArcticSpider '340'. Running at 24V you are at 75% Imax and can take your load to -10C while burning about 300W.

Now let's say you want to turn the TEC 'OFF'. Instead of cutting power, set the voltage at 5V. Now the TEC will draw only 3A, for a total load of only 15W. It will not provide any cooling, but it will move over 100W at about zero differential - in other words, it's just along for the ride but uses almost no power and generates almost no heat. CoP at that voltage and Imax is over 6 which is why your 15W will keep the TEC in 'neutral' territory.

You can do the same thing with the 127 element TECs like the ones on eBay - but go to 3.3V for the 'OFF' state.

That is very easy to do and a lot easier than an exotic hookup.

[littleowl]

TECs are good insulators so you can't turn it 'OFF' - but there is another way to get a similar result.

TECs transfer the most power at zero temp differential. Let's say you want to cool a 100W heat source and are using the ArcticSpider '340'. Running at 24V you are at 75% Imax and can take your load to -10C while burning about 300W.

Now let's say you want to turn the TEC 'OFF'. Instead of cutting power, set the voltage at 5V. Now the TEC will draw only 3A, for a total load of only 15W. It will not provide any cooling, but it will move over 100W at about zero differential - in other words, it's just along for the ride but uses almost no power and generates almost no heat. CoP at that voltage and Imax is over 6 which is why your 15W will keep the TEC in 'neutral' territory.

You can do the same thing with the 127 element TECs like the ones on eBay - but go to 3.3V for the 'OFF' state.

That is very easy to do and a lot easier than an exotic hookup.

but at the same time your cpu heat would over ride the tec..?? I know when I had it on my 3200+ I killed a 226w because I ran it to low to much.

[zipdogso]

but at the same time your cpu heat would over ride the tec..?? I know when I had it on my 3200+ I killed a 226w because I ran it to low to much.

Yeah...at first I see your point littleowl, but I think Uncle jimbo is suggesting the "hybrid" option (up the thread a bit.) so the CPU would be getting water cooling when the TEC is "OFF" as it were.

A "hybrid" TEC/waterblock is something I have been wondering about as a possible solution to big heat outputs of quads etc. if one has to take watercooling to the CPU for the TEC anyway, what about using some of it to assist the TEC and actually cool the CPU somehow. It would require a custom waterblock build and perhaps a complicated one at that.

[Uncle Jimbo]

Yeah...at first I see your point littleowl, but I think Uncle jimbo is suggesting the "hybrid" option (up the thread a bit.) so the CPU would be getting water cooling when the TEC is "OFF" as it were.

A "hybrid" TEC/waterblock is something I have been wondering about as a possible solution to big heat outputs of quads etc. if one has to take watercooling to the CPU for the TEC anyway, what about using some of it to assist the TEC and actually cool the CPU somehow. It would require a custom waterblock build and perhaps a complicated one at that.

The idea is that you have enough cooling without the TEC to run at lower power, and can crank up the TEC when needed. You can read the amount of added cooling you will get from the TEC curves. You just need to keep enough power on the TEC in the low power state to keep it from being an insulator.

The TEC needs to be big enough to pass the heat in low power state - but since they are so much more efficient at low power, that is usually not an issue. Several commercial designs use this technique.