Concrete Slab water cooler loop - Hooked up!!!

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. No need for radiators or fans with chilled water coming straight out of the slab Hope there isnt any condensation issues but I dont think the water will be cold enough....

Any ideas on how I can measure the heat in watts that this can obsorb over a period of 3hrs? some pics:


Click to view full size!


Click to view full size!

----------------------------

Results are in:

here are the results for today:

• test start time 9am
  
• Water temp at start 10 deg (after 10min of running the pump with no heat load).
  
• Water volume in the revserve 2litres, water volume in the loop .5 to 1 litre. Total volume 2.5 to 3 litres.
  
• Heat load 150 watt fish tank heater. This will simulate very closely the heat load I will be putting on the system as i7 creates about 130 watts of heat.

The test system is still running but I don't think it will change from 17 deg that it has been running for the last 4 hours+


Click to view full size!


So what does this test tell me / what can I expect?


Firstly, Tasmanian agricultural areas (soil) have a mean annual temperature of 11-13 deg C. So I can expect the concrete foundation to sit at about 14-16 deg year round. When the house is built adding a few deg for ambient heat in the house. I have shown that this system will hold 150 watt load at about +7 deg above concrete temperature.

So I can expect water for my PC cooling loop to be about 21-23 deg C year round. I was hoping for a bit lower in the range of 16 deg and I'm sure this would be possible with a longer loop.

My current water loop (standard setup with 120.3 radiator and CPU block) sits at about 10 deg above ambient air temp giving me 29-31 deg C coolant temp.

After all those variables are taken into account. I can expect to have chilled water 8-10 deg C below my current water loop which should give me quite a lot more head room for overclocking and best of all NO NOISY FANS blasting air through a heat exchanger.

A big thanks to the people that posted constructive comments and offered help with this project


Click to view full size!


Click to view full size!


Click to view full size!

 

No idea on measuring, but it should work well...
Love the "forward thinking" though...

 

That's extreme! Can't wait to see the results!

 

How much water will be in the loop in total?
I assume you are also putting a tank of some sort down there as well?

 

Great idea, but your going to need a good pump to keep a steady flow. Can't wait to see what temps you get though.

 

Thanks JTF

Yer Millsy me too. TF2 will run sweet as lol

I have to measure it but I think about 3 litres. Im gonna have a reserve above ground probably on the floor next to the pump.

I was thinking a decent aquarium / pond pump like an ehim 1260 or similar should be up to. The head will only be about 1200mm so its not a big task for a decent pump. Just have to find a nice quiet one

 

These pumps seem like the go. About $150 - $200, 3m head, low wattage (30watts), adjustable water output and silent.

http://www.eheim.com/base/eheim/inhalte/indexbc94.html?key=liniendetail_28394_ehen

 

Reliable pumps,
Are you going to use it just to circulate the loop and tank, or the whole system ?

 

You know I have always considered that as an option in a new house, just never quite got there.

What I have also thought about it running some copper pipe through the wooden floors and under the house to put the radiator, fan and pump under the floor where it's much cooler than inside AND where it just doesn't matter how much noise it makes (within reason).

 

Nice 1 but will this effect the slab in any way and the warranty on ur new home?
Might wanna check that out .... Other wise niceeeeeeeeeeeeeeeeeeeeeeee

 

Was gonna circulate the whole system with the one pump. The less pumps in the system the less heat they can xfer into the loop.

Oh well maybe next time you build

I think running copper in a slab is nothing too unusual. I'm doing the house as owner builder so warranty is not a problem The tradies are like WTF though and Im going to separate the copper so that it is not touching the steel reinforcing bar.

 

Depends what, and how many, waterblocks you're going to use, flow through the blocks makes a reasonable difference, you could always use the smaller of the 3 pumps you listed inside a reservoir, then run a little Mcp355 for the Pc loop...
Then you can have the 240v pump running all the time (saves having to remember to switch it on)..

 

Make sure council and the completion certificate guy don't see it or you will be ripping that slab up and re pouring the entire section. Because what you've done right there while ingenious is illegal in the eyes of the scum.

 

Who turns it off?

But yeah, I'd be interested in how you build this loop, personally I would probably set up some sort of tank being circulated through the loop in the slab, and a secondary loop feeding out of the tank.
Though then I might get lazy and just plumb the loop straight into the computer

Do tell!

 

Interesting idea to use it for cooling your PC, make sure the sides of your slap are shielded from the sun and you can expect slap temps of as low as 12 degrees most days and often cooler depending on your climate, due to the volume it should be quite effective at drawing the heat out of the water you pump through it though I would consider running a few more loops. A better option than copper is to use PEX piping which is used in radiant floor heating set ups, it won't corrode or crack/rupture as the slap expands and contracts and you can loop it around much easier than copper but it doesn't have the thermal transfer of copper so that would be a downside. Only downside is your limited to setting your PC up there and what do you do if you ever want to move it or take it over to someones for a lan? Do you have a standard radiator somewhere?

 

Yer thats a good idea. At this stageits just gonna be CPU and maybe GPU but who knows by the time I have finished building the house...

Some good info here: http://www.copper.org/applications/plumbing/techcorner/problem_embedding_copper_concrete.html

well I just planned to do the one loop but your idea of running a secondary loop out of the reserve is a good idea... thanks dazzawul

Anyone got any ideas on setting up a test to work out how many heat watts this loop can take?

 

Just a thought... perhaps you could put some chairs under it so it will be entirely encased in concrete rather than sitting on the plastic and sand.

 

I would have thought that copper pipe full of air would be less dense than concrete, so it'd actually float. You'd just have to push it down a bit to make sure it stayed below the surface.

 

It would be less dense. But concrete is viscous enough that it wont likely float to the surface unless the concrete is vibrated. Which most house slabs arent these days. I am yet to see an underslab copper pipe float to the surface. Nor will it come up through the weight of the rio mesh. If you want to be sure this doesnt happen, you could use some twitch wire to tie the pipe to the rio mesh, thus ensuring it doesnt sink nor float.

 

yes agreed! I plan to tie it down and use "chairs" to keep it in place so that it is completely encased with concrete. Here is the house plan and we have made a study for all my "computer junk" as the wife calls it so the pipe will come up next to the stud wall under the desk that is going to be built in.


Click to view full size!