Head in a closed system?

Hi!

I'm currently working on my house, and making it "computer friendly" is a big concern for me. Naturally I want everything to be as quiet as possible, while running as cool as possible.

So, I got this cellar.. Or, well, it's about a meter from the ground to the roof, so it's more like a.. well.. suddenly my english dried up. But you get it, it's just a space under the house, not useable for anything!

So, some copper tubing semented to the ground? To get adequate cooling, I'm thinking about quite some length, about 10m of 15mm tubing. But my workarea will be on the first floor, so it's about 3,5 meter straight up!

But a pump with, say 3 meters of head should still work, right? As the water coming down balances it all out and the whole loop acts as it has no head (apart from "tube friction"..)

Oh, and is it worth it to go for 22mm copper tubing instead of the 15mm?

And the pump will also stay in the cellar, and reconmendations? Got an extra AquaBee 2000/1 (2000l/h with 3.0m head) and that might work?

The word is "crawlspace."
Nasty cramped, uncomfortable places to work- but perfect for mounting a ground-cooling loop!

In a closed loop the head will pretty much be a non-issue- correct.

There will be some effect from having very long tube lengths though, and for that reason I do suggest using the larger size tube. It will cost more but help to keep flow rates up throughout the loop.

I am not familiar with the pump you mention, but my guess is that it will do ok.
If you have problems maintaining flow with it, using a second pump as a booster (upstairs perhaps?) might help. (That is pure speculation though! I've never tried a system with two decent pumps.)

Yes, the price difference isn't great, so then I'll go for the 22mm tubing.

Can't wait to get this done..