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Using a House's Concrete Foundation To Cool a PC
Agg writes "Well the slab gets poured on Wednesday so I thought I would sink 6 meters of copper pipe in the slab so that I can run my water loop through it when the house is finished. I hope to have water year round at about 16deg [about 61F]. No need for radiators or fans with chilled water coming straight out of the slab!"
How are you going to explain that if you want to sell that house???
Ahhh...the great dumpster continuum. Many a free computer will be found there. -- sowth (748135)
The steel rebar and the copper pipe being in close proximity will make them act as electrodes on a battery. This will cause the steel anode to slowly be destroyed by the chemical reaction.
Is it a practical concern in your case? I doubt it, but if they haven't poured yet, it wouldn't hurt to wrap the copper pipe in some PVC tape. This will reduce the thermal coefficient though. Maybe just do it where it passes within a couple inches of the rebar.
Use PEX instead. Copper will eventually fail. Look at the material that is used for radiant flooring.
Without proper thermal throttling, your roof could come off, even with a passive heatsink.
I think Antec makes a two-story-high fan that might work perfectly in such a situation, but the neighbors might be bothered by the LEDs.
6 ft down doesn't actually provide much cooling. If you want a "neutral" temp, you need to go well underneath the slab.
Plus, you're "sinking" to a temp of 40-50F, and you have to consider that the concrete itself is a fair insulator, so you won't actually lose as much heat as you hope.
Ground Source heating/cooling is a pretty nifty technology, and can be applied to a whole house HVAC system, rather than just a computer. It obviously requires more tubing than a single computer would, and in most climate will still require some supplemental heating/cooling for more extreme temperature days, but it's still awesome. It does have some upfront costs though.
This idea to do it for a particular computer is a clever idea. I personally wouldn't want the pipe to actually be moving horizontally through my slab, I'd rather dig as small a diameter hole as is possible, but deeper under the slab, and just have the line penetrate the slab vertically. The deeper you go, the more stable the temperature becomes, and the less hollow copper pipe you've got running through the slab, the less you weaken it.
One time I threw a brick at a duck.
Why? It's very similar to what they do when laying radiant heat into the floor (which is very nice btw, over ducted heat, helps with breathing problems).
Also, like a previous comment suggesting, maybe you should look into radiant heat tubing over copper.
Houses have been built with copper pipes and steel rebar and rewire in the slab for decades now without any electrolytic effects showing up.
Once the concrete is cured, it is no longer an electrolyte. Concrete is not a great electrical insulator, but it's not a great conductor either.
Putting moderation advice in your
Getting rid of heat by dumping it into the ground is a great idea.
The problem is, you're dumping heat into your house's slab, not the ground. You need to put the pipes several feet underground.
All this is is a mild underfloor heating system. If that's what you're trying to achieve, ok, but if you're also paying for air conditioning to remove heat from the house, this is probably not worth it.
Putting moderation advice in your
Negative.
http://www.copper.org/applications/plumbing/techcorner/problem_embedding_copper_concrete.html
They use PEX because it is cheaper and easier to install, NOT because of its longevity.
"As God is my witness, I thought turkeys could fly." A. Carlson
I got a bunch of raised eyebrows when I had two four-gang electrical outlets (one from either leg of the house power) and an exhaust vent fan installed in one of my closets when we built our house. I wanted it for a server farm but couldn't convince anyone that I wasn't going to be farming something else.
The cost of that cleanup, of course, will be borne by taxpayers, not industry.
Well, your habit of using the acronym "THC/IP" did rather give the game away....
"Also, like a previous comment suggesting, maybe you should look into radiant heat tubing over copper."
This. I used to live in Alaska and radiant heat slabs were very common. The problem was making sure they never went without heat in the winter. If they did, you ended up with burst pipes and a cracked slab. Big headache.
The fix is burst-resistant flexible tubing. There is a product called Aqua-pex that fits the bill perfectly. Does not burst when frozen, has a 100-year warranty and is easy to install as it is flexible.
The other problem with copper in concrete is that the concrete itself is corrosive. It WILL eventually eat through the pipes leading to all sorts of headaches. Usually, when this happens the only fix is drain them and cap the pipes. Most people in Alaska with radiant flooring, even when using Aqua-pex, lay down a second circuit in case there is a problem. They simply hook up the back-up.
Another suggestion. If you DO use copper tubing, use alcohol, or some other coolant such as glycol, rather then water. You will have better heat transfer as well as less corrosion. This is, of course, assuming you have a closed loop circuit (would be foolish to have anything but).
There is a data center in WA state that keeps half of its' property as vacant land for the sole purpose of using it as a giant heat exchanger. Looks like about an acre. They have piping about 16 inches underground throughout the field. I am told it works great.
I judt got a nre Kinesis keybiartf so please excusr ant egregiou typos.
You've obviously never been lied to about birth control then.
That is why I wondered why some data corp hasn't bought up the old Titan 2 missile silos we have here in AR and turned them into datacenters. They are VERY deep in the ground, so you have natural cooling there, they are on the side of a mountain with lots of wind, more cooling, and if you put the racks into the silos themselves you could have fresh air blowing straight up and out through the silos. there are also lots of fiber lines running through that area, including dark fiber left by the telecos during the dotbomb. Not to mention with those big steel doors and hardened everything breaking into your data center would be pretty damned difficult, if not impossible. Oh and we have nuclear power here, so electricity is cheap compared to surrounding states.
It always seemed to me that with datacenters needing so much cooling these would be a natural fit. The military has done all the hard work, and from what I heard they sell them pretty cheap. One guy even bought one and turned it into an underground house for his family. Just always seemed to me to be the way to go.
ACs don't waste your time replying, your posts are never seen by me.