External multi-pc cooling plan
 

For a while I’ve been thinking about this project but now that I’m (hopefully) moving to a suitable house it might be time to put it into effect.

The idea is to have each computer drawing cooled water form one tank and returning it to a second. A separate loop system would pump out of the ‘hot’ tank to some radiator arrangement (outside the house, I was thinking) and back to the ‘cold’ tank. There would be a dual overflow arrangement so that if the external pump managed a greater flow rate than the pumps for the computers, the ‘cold’ tank would overflow to the ‘hot’ tank and vice-versa.

Now in the house I’m trying to buy, I could mount the radiator arrangement on the north-facing wall, so as to be in shade, or in the garage, so the sound is further muffled if that doesn’t get too hot. I was thinking that the external elements (pumps, fans) would be mains voltage and I’d gradually work in some automation (having the pump switch on if the water temp in the tank went above ambient or similar and having the fans turn on only if required. Maybe in winter it would run passive.

Now the cooling loop doesn’t have to fit in a PC so I can use larger pipe/hose and cooling elements that you’d normally see. The pump would hopefully not have to manage a huge head, if there are no waterblocks, but a high flow rate would be useful. Thus I’m vaguely thinking of a 1260 or equivalent. However I have no idea what sort of radiators I should be looking at.

Do I need to look for bits from air conditioning units or car radiators and if I do will any of this be able to run passive or would I be want a different radiator for passive cooling and have some kind of arrangement with electrically operated valves to use a different rad when the outside temp was low enough.

The result would be that I wouldn’t need to have any radiators or reservoirs in the individual boxes freeing up a lot of space. I think you can also see it would be interesting from control/monitoring aspect. If required I wouldn’t mind having a small box (I’m awash with MATX P3 boards) to control the whole business as I rather keen on lots of readouts from my cooling rigs.

Obviously this is a big project and will be a while in planning, and there a plenty of issues (antifreeze in winter for one) but I’d like whatever advice you guys can offer.

Each PC gets its own 12v pump, so each is only cooled when on?
Disconnectable fittings are available - they leak a ml or two when disconnected, but so little that a little rag underneath is enough - but put them outside each case.
Radiators mounted flat are better than vertically - allows hot air to rise etc.
If you garage is nice and drafty I'd probably mount one or two car radiators up in the rafters.
You'd definately need antifreeze in the loop.

if you're going for a built-into-the-house type of deal, you might want to think about just a buried length of copper piping. underground temps are fairly regular (lower than air in the summer, warmer than air in the winter). Just a thought.

I've seen a couple versions of this and all seem to be excellent solutions! I especially like the OP's dual tank idea!

I'm afraid digging up the garden will not be an option, though if suitable buiding work ever happened I'm try and get a tank in there.

Is the car rad the way forward for both passive and active cooling here? Size is not an issue, I'd think and I'm willing to have both passive and active cooling, but at the same time don't want the garage to sound like I have a machine shop running in there.

Also pump advice?

Well maybe more than one pump, I'm a bit keen on parallel loops and I wouldn't need reperate radiators.
Yep, there are a huge selection available, but are they going to be very restrictive?
Alas the roof of the garage is boxed in as storage. In any case I'm going to log some daytime temps in there before I decide to use that location.
For winter at least, maybe I should change the water spring and autumn ;)