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# Powering Thermoelectric Module (Peltier) Answered

I am trying to understand how TEC modules work, and I think I have it figured out now, but was hoping that someone with more electrical knowledge could verify that I have it right.

I am looking at this TEC module. My current understanding of this is as follows:
1. If I regulate the current to this module to a max of 2A, the maximum amount of heat that the module will move at DTmax = 0 would be approximately 75W.
2. If I regulate the current to this module to a max of 2A, the module will not exceed a DT of ~20C.
3. If I regulate the current to this module to a max of 2A, the voltage could range between ~4-6V, but would not reach 10V due to the limitation of DT.
4. Therefore, this module, limited to a max of 2A, would use at max 12W (approximately).

Is that all correct?

Second, I am comparing the above module to this TEC module. For this second model, my understanding is:
1. If I regulate the voltage to this module to a max of 12V, the maximum amount of heat that the module will move at DTmax = 0 would be 28W.
2. If I regulate the voltage to this module to a max of 12V, the module will reach its DTmax of 67C (theoretically).
3. If I regulate the voltage to this module to a max of 12V, the current could range between ~0.75-1A, but would not reach 2A due to the limitation on voltage.
4. Therefore, this module, limited to a max of 12V, would use at max 12W (approximately).

So basically, it is a trade-off between DTmax and heat moved at the same wattage. Is that correct?

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## 10 Replies

Seems like a waste to have two systems like that...

Why not just plumb (Reservoir > pump > Cpu(and or)Gpu water block > Tec water block > Reservoir?)

Replace the Radiator with a extra water block that will attach to the Tec ! then attach it to a Big Heatsink + a Fan. You could even keep the Radiator for passive cooling while watching Vid's or cruzing I'bles then turn on the Tec for your Gaming and or Video Editing :D

For Powering / Regulating the Tec, I would Strongly Suggest you put a Temp sensor on the Water Blocks and use it to turn the Tec on and off as needed.

eblingdp (author)2015-04-16

No I only plan to have one system (either a single loop or a dual loop, whichever is more effective). The goal of this project is to reduce the coolant temperature as it goes to the components to sub-ambient (possibly even sub-zero) temperatures for sustained extreme overclocking. The coolant will probably be a mixture of water and methanol to maintain high thermal properties while preventing freezing or high viscosity. Because methanol is highly toxic, the entire system must be completely sealed to prevent any form of evaporation (so probably no reservoir). Due to the amount of energy required by the TECs to force the coolant temperatures down to very low temps, cooling the TECs with heatsinks simply isn't going to cut it. I'm probably looking at around 3-4 MO-RA3's just to dissipate all the energy going into the system.

Wired_Mist (author)2015-04-16

Well if you like Overkill; Have fun ! lmao

Still try to use a Temperature sensor on each main Water block so you can know the temp. it will help you manage the system and see whats going on. Also I'd lean to the single loop system for reliability.

Just for Fun, try punching "phase change Cpu cooler" into Google for some Truly Epic Cooling !

eblingdp (author)2015-04-16

Phase change is too loud and only cools CPU. :P

And yeah, there will be inline temp monitors throughout the system.

eblingdp (author)2015-04-16

These are some initial designs for the custom blocks I'm ordering for the project. Using emachineshop. It's pretty cool. Going to prototype in something cheap to test it out first before I go for the actual copper blocks. Still need to tweak a few things, like I forgot space for an o-ring between the parts. Thinking I'll be using a 207 fluorosilicone o-ring, and if I'm changing from the 50x50mm to the 40x40mm TECs I'll have to tweak the dimensions. Planning to use 7 of these total, so 3 cold blocks and 4 hot blocks, 24 TECs. Altogether it shouldn't be bigger than about 8x5x5in. These blocks will allow me to compress the TECs as well. :)

Wired_Mist (author)2015-04-16

Damm lol Be sure to take some Photo's; Love to See an I'ble from this.

Good Luck :D

eblingdp (author)2015-04-14

Ok thank you. I have one more question although I'm not sure this is the right place to ask it. For a water chiller application with a loop that looked like the one outlined below, which would be better, more heat moved, or higher DT?

That is simplified but it's the general idea...

mpilchfamily (author)2015-04-14

The peltier would be more effective cooling the CPU directly rather than chilling the water. If you have multiple items to cool then get multiple peltiers and use the water loop to cool the hot side of the peltiers.

If you where using it to chill something like a can of soda then you'll want a lower temp. No major heat is being added to the drink other than the ambient air. So it's a matter of time before the drink reaches equilibrium with the peltier.

In the case of cooling a CPU. The CPU is constantly pumping out heat. So the faster you can move that heat away from it the cooler the CPU will remain. But the faster the peltier can move the heat from the cool side to the hot side the cooler the cool side will be.

eblingdp (author)2015-04-15

I'm aware that it is usually more effective to place the TEC directly on the components, however, there are certain problems with doing that when the temperatures are below dew/freezing point, which is what I want to attempt with a chiller. I could explain more if you'd like but that's the general idea.

So, there are basically two designs I am looking at, a single-loop system and a dual-loop system. I've attached diagrams of each. (The part of the diagram that shows the TECs and waterblocks is able to be iterated for more blocks/TECs as needed).

My guess from what I posted above is that, in a single-loop system, the TECs that move more heat would be more effective, while in a dual-loop system, the TECs that can reach the higher DT would be more effective. Does that sound right?

steveastrouk (author)2015-04-14

Yes.