Question PC radiator and fans outside in AZ desert?

fcar1999ta

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Apr 24, 2014
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Thinking of piping the radiator and fans for my PC outside just to get the heat out of the house. I doubt there will be any risk of condinsation during the winter, since temps are never below freezing when the computer is on.

Inputs?
 
If you want to look at crazy stuff like this you can watch the linus tech tips videos, he did it in canada and uses his pool to cool it.

I think the larger issue is going to be in the summer. Arizona gets well over 40c outside. Although this is still less than the temp of your cpu it is going to greatly reduce the ability of the cooling.

Then again you are likely going to have to use some custom water solution and they make very big radiators so you can dump more total heat.

Can you do it I guess. You are going to have to compare the cost of water cooling equipment to the extra air conditioning costs to just run it inside your house.
In the winter technically you save a bit of money if you use your computer to also heat the house.
 

NedSmelly

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Just keep in mind Poiseuille’s Law - flow resistance increases with length. So you will need to factor this into your calculations and assess whether the pump is strong enough if you extend the tubing,

Also should consider insulating the tubing as it travels to the radiator - otherwise the tubes themselves will act as heat conductors. Which is what Linus screwed up with his early efforts.
 
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Paperdoc

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Your thinking may be unduly influenced by your experience with home Air Conditioning. That is ALWAYS done with a powered module outside the house that uses a fan to exhaust heated air. But the overall mechanism is much more complex. That unit outside contains a compressor that accepts warm refrigerant gas from the Evaporator Coil in the inside unit (whether that also contains a furnace or not) and compresses it to a much higher pressure. Under these higher pressure conditions that refrigerant gas is at even higher temperatures - much hotter that the outside air. THEN the hot gas is passed through a Condenser (heat exchanger) that has a fan blowing warm outside air over it. However the warm air is still MUCH cooler than the hot compressed gas inside, so heat IS removed from the gas, reducing its energy content so low that it condenses into a liquid form. The heat energy removed is the Heat of Vaporization of the refrigerant - that is, the difference in heat energy between the liquid and gaseous forms of that material. The resulting liquid has a temperature just a bit higher than the outside air that cooled it. So the cooled liquid then flows through a high-pressure pipe back to the interior cooling system. It is fed into the Evaporator (another heat exchanger) inside that through an Expansion Valve that restricts the rate of flow of the liquid into the Evaporator, so that the Pressure inside the Evaporator is MUCH lower than in the high-pressure liquid line. This allows the liquid to evaporate into a gas again. To do that it requres heat, so the gas gets very cold, and the in-the-house air blowing (by fan) through the inside unit then is chilled a lot by the cold Evaporation fins. This move heat from the room air into the refrigerant gas. The final result in here is that the gas is now re-warmed and heads back to the outside Compressor unit.

The key point here is that a refrigeration unit uses devices to cause CHANGES of STATE (between liquid and gas forms) of the refrigerant material at TWO places. In each location the heat exchanger has a hot side and a cold side so that the AIR passing over it is COOLED inside the house and HEATED outside the house. In both locations there is a big temperture difference created by the system to maxmize the rate of heat transfer.

A computer liquid-cooling system is a MUCH simpler system. It uses a liquid that never changes its form to absorb heat from the CPU chip with a modest temperture difference - the CPU interior temp can get up to 100 C at worst - and the heated liquid leaving the contact block on the way to the cooling rad is just a bit above room temperature. That's a fair temp difference. But when that fluid passes though the rad and is cooled by room air, cooling can happen only to the point that the cooled liquid coming BACK from the rad is only a couple degrees warmer than the AIR used to cool the rad. This system cannot move a LOT of heat rapidly, and is limited by how cool the room air is.

Bear this in mind also. A CPU may be the hottest chip in your machine (the GPU chip wull be close to that, too), but the highest-power CPU chips now in common use convert into heat at a maximum rate of 150 W, and AVERAGE heat generation is lower. That is the same as the heat generated by ONE traditional incandescent lamp of 100 W to 150 W. Few people would go to a lot of effort to design a system to move that small amount of heat outside.
 
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fcar1999ta

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Maybe just moving the radiator and fans to the hallway, instead of outside. I know that I would need multiple pumps due to the length, probably one at each end.
 
I am unclear what you goal is.

In the end the heat goes from the CPU to the air in your house which is then removed to the outside by the air conditioning.

In a way you are cooling your pc with the house air conditioning.

I am not so sure it matters where you place the radiator inside the house. If the computer is making one room too hot maybe simple fans to move the air to a different room. I guess you could do crazy stuff like place the radiator in front of one of the ac cooling duct.

In the end I strongly suspect you can buy a small window AC unit to add extra cooling to the room with the computer for less than it is going to cost you for all the tubing and pumps to make some fancy solution. Also it is going to be much more reliable. Custom water cooling solution on pc require a lot of maintenance because of the degradation of the cooling solution and even the metals in the cpu blocks and radiators. You also run the risk of some tiny leak destroying your pc.
 

Ralston18

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Full system hardware specs and OS information?

What are the temperatures and temperature ranges being measured for the system, CPU, GPU, etc.?

What/why is the CPU getting so hot that "external" cooling is being considered?

Is the system being used for heavy gaming, video editing, or even bit-mining?

I suggest a few photographs showing case, all fans, airflows, etc..

Post the photographs here via imgur (www.imgur.com).

Very possible that someone may spot some relevant issue or concern.