Guide to changing the MCW50-T pelt to a 172w

[Major]

I was asked to provide some instructions on a different forum so I thought I'd write a short guide.

Temps are significantly better running a 172w pelt in the MCW50-T, but using it at 24v produces alot of heat in the coolant. I ran mine at 18v for the most part and found that to be a good compromise between cooling ability and heat production.

You can buy a 40x40x3.2mm 172w pelt from dangerden http://www.dangerden.com/mall/Pelts/peltiers.asp

It requires 24v to operate at 172w, you can run it at 12v at roughly 90w still better than the factory pelt in the MCW50-T

Replacing the orginal pelt is pretty easy:

1) Remove the foam insulation on the bottom of the MCW50-T, not all of the foam, only the part that overlaps on the bottom of the block. Try to remove it without damaging it. I used a sharp razor blade and just cut it off in one peice so that it can be reused.

2) Remove the hex head bolts holding the cold plate to the bottom of the block.

3) Remove the cold plate, the old pelt may come out stuck to the cold plate. PAY ATTENTION TO THE RED WIRE ON THE OLD PELT, THE NEW PELT MUST BE INSTALLED WITH THE RED WIRE IN THE SAME PLACE If you put a pelt down in front of you with the red wire on your right, the part of the pelt that is facing upward will be the COLD side and the side facing downard is the HOT side !

4) Remove the pelt, use caution not to tear the rubber gourmet that goes between the MCW50-T and the pelt as this is the only thing that prevents the wb from leaking. The surface of the pelt is directly exposed to the water in the block. You will see what I'm refering too once you open it up.

5) Place the new pelt in the rubber gourmet. DOUBLE CHECK TO BE SURE THAT THE COLD SIDE IS FACING YOU

6) Lightly cover the the surface of the pelt that is going to be against the cold plate with thermal compond (I use Ceramique). I think the best aproach is just to lightly haze the surface of both the cold plate and the pelt.

7) Replace the cold plate and tighten down the hex head screws ( Don't overtighten they can break/strip )

8) Replace the lower portion of the foam insulation you removed, I used RTV silicone to stick it back to the foam insulation that was left covering the sides of the waterblock.

Thats it ! I hope this helps, its easier than it sounds

[Jabo]

Wow, ya da man, Major Slaughter!
I owe you one for sure, fantastic guide, matey ! Very much appreciated!

As soon as I get some £££ I will do this since 176w pelt is not that expensive and only requires some time to be done (and memorising of your guide, of course).

Fantastic work, thak you again

[Major]

NP, I wish I had some pics

[Holst]

Is point 3 allways true?

I have to write a small C on the cold side of mine in permanent marker (or sove a 9v battery over them and see which side gets hotter)

[Major]

To my knowledge all pelt modules are designed this way, I've yet to find one that wasn't.

Here is a link with some semi-in-depth info on pelt theory and it states the same rule of thumb:

Leads to the modules are attached to pads on the hot side ceramic. If the module is sealed you can determine the hot side without applying power. With the module on a flat surface, point the leads toward you with the positive lead, usually in red wire insulation, on the right. The bottom surface will be the hot side.

http://www.electracool.com/moduleworking.htm

[Jabo]

Originally posted by Major Slaughter
To my knowledge all pelt modules are designed this way, I've yet to find one that wasn't.

Here is a link with some semi-in-depth info on pelt theory and it states the same rule of thumb:




http://www.electracool.com/moduleworking.htm

That's a trully scientific method LOL LOL LOL
He he he, great stuff

Here is a link to one of my threads containing ~6 different links to more TEC knowledge almost anyone could be bothered to read.
I found all answers there

Have fun.

[drunkenmaster]

Hi Major, was thinking of doing this shortly, and am thinking of running at 13v. I have a 3-15v switching psu i was gonna use for my 226w cpu pelt(brought like a year ago, thought better, tried to sell forgot, found, thinking bout it again :p ). it can take 40amp's(maybe 45) so will be fine with those two pelts. 13v sounds like the sweet spot from you guys.

Thing is i'm trying to work out how much better than the stock 80w pelt is. Thing is, i've been trying to use this guide http://www.ocfaq.com/article.php/cooling/extreme/tec/58
to work out power of a 226 at certain volts, and same for teh 172 24v and i come out with strange answers. Are those calc's accurate, them seem so, but i get odd results. If i was using 13v on that 226 pelt it would seem to provide 193W cooling power, and require 266W to run the pelt. thats fine.

but if i choose 8v it will give 118W cooling, and require 100W to run the pelt, which seems very obviously flawed. The reason that worried me, and the reason i checked that is that the 172W 24.6V pelt seems to provide a touch over 90W cooling, but again only says 77.6W to run? So are teh numbers right but the power needed doesn't quite work right, or is the ampage wrong?

Just wanted to check.

Also the swiffy 80W pelt is rated 15.2v Imax at 80.3W 8 A.

which at 12v is only actually giving 63.3W of cooling? draining 6.3 amps and 76W off the PSU? If thats all right cooling powers but the rest is just not quite accurate power needed. Then a 172W provides about 50% better cooling power overall? If so i'll try that. What about a 156w 40x40mm pelt or a 120w. not much choice in the UK, any good US sites that you can think stocks them?

Cheers

[KnightElite]

I may have to rewrite that article. You appear to have found a flaw in it.

This stems from the non-linearity of the semiconductors used to manufacture TECs. I was making some assumptions, namely that a TEC could be treated like a resistor, which apparently turn out to be way off.

You will not, regardless of what my math says, ever get a situation where Q is higher than P. You should check out a piece of software called Kryotherm, it has all the information to do the math for you for TECs up to 226W.

[]JR[]

Whats your definition of P Knight?

Point 3 is somewhat mute, since if you put the tec in the wrong way up, you can just wire it up backwards and then the other side becomes the coldside

And dont forget different manufacturers put the wires on the other way too...

]JR[

[drunkenmaster]

I think Major was saying for point three that, every pelt should be the same way, regardless of manu, like an international standard type thing. But yeah, you can just wire up the other way, but its easier to work it out before hand.

Knight, yeah, not having a go or anything. I was just really wondering exactly what kinda power i'd be getting. Do teh none power usage numbers seem right though, the amount of power at any given point, are they likely to be accurate. Also, the power used, i guess its inaccurate because tecs are very inefficient over those last few volts giving minimal cooling power boost at say 15.2v over 14v due to extra heat and so on.

TBH, i've always forgotten to check, and it seems quite odd that people get such good cooling off the plain mc p 50-t as it really can't be doing much more than 60w's cooling, and that core at 500+ on a9800 pro must be very close to outputing that much.


Was also trying to work out what a 226W will give fully, i'm still reading through threads here, what kinda temps would people get say on a P4 at 3.8-4Ghz with a 226 @ 13v? I'm not sure who said it be there was mention that a decent 2x172 set up could give you vapochill matching cooling? Anyone tried a 2x226W and gotten good temps. I can get rads to get rid of the heat, thats not a problem, though i'm thinking it would warrant a custom, fairly unrestrictive + huge pump if not using a waterchiller?

[drunkenmaster]

do'h, jsut remembered 172W 24volters are like 40x40, i'd guess the maze 2.2 can only take 2 of them and not 2x50mm?

[Pimpsho]

how would i get 24v?!! i mean normal psu's only put out a lil over 12v at the most... major what did u use to power the tec bro

[KnightElite]

Originally posted by Pimpsho
how would i get 24v?!! i mean normal psu's only put out a lil over 12v at the most... major what did u use to power the tec bro

For TECs of this calibre, you want a dedicated power supply, which can be had in pretty much any voltage.

[Pimpsho]

ya im gettin the meanwell s240... but i dont get how he got his 12 up to 24.. my meanwell 320 can only hit 13.6 ish...

[kraggy]

Originally posted by Pimpsho
ya im gettin the meanwell s240... but i dont get how he got his 12 up to 24.. my meanwell 320 can only hit 13.6 ish...

You get a Mean Well S-240-24....which is a 24v pSU.


Does anyone know about the adjustable pot on the S-240-24 Mean Well? I mean how far it adjusts the rated voltage down? Because I have a 24v 172w pelt that I am going to swap out my 80w pelt in my Swifty. I want to be able to run the TEC at about 18 -19v. I turn the pot with out plugging it in and it doesn't turn very far at all. I really don't know if my BIX rad will be able to dissapate the heatload of a full bore 24v 172w TEC?

[Pimpsho]

u dont need to turn the pot adjustmate far at all.....and do it while the psu is on so u can read the volts that its outputting i use just a normal multimeter..

[NinCom]

Where do i get a mean well s240 ? Some store that can ship to Europe ?

[kraggy]

Originally posted by NinCom
Where do i get a mean well s240 ? Some store that can ship to Europe ?

I got mine off ebay.com for $35!!!

[kommando]

need some piccies, i don't understand it tooo mcuh.

[sandman]

So, the TEC actually touches the water?

So the MCW50-T isn't just a MCW50 with a coldplate and holes in the bottom for hex-head screws?

This I did not know.

[kraggy]

Thats what it sounds like from Major's nice walkthrough. I'll be finding out tomorrow first hand. Thats when my new rad comes in and I will rebuild/replace my old GPU/TEC setup.

OLD:
80w TEC
MCP300 pump
BIX rad


NEW:
172w TEC W/S-240-24 Mean Well
MCX600 pump
Chevte Heatercore

[sandman]

Alright, make sure to say. I'll be waiting.

[KnightElite]

Yeah, that's correct. The TEC is in actual contact with the water.

[sandman]

That's wierd.....seems to me that wouldn't be a good thing. But, whatever works.

[Soulburner]

Can any VGA blocks fit a 50mm TEC?

I don't want to run the 172w 24v 40x40 TEC at only 12v......so I am looking at a 169w 15v 50x50....I think at 12v it would do much better than the 172 at 12v....but would it fit?