Need advice on setup with ground water cooling

[wildmandnd]

Hey guys,

My last PC had dual Reserator1 for a truly silent gaming, but that was over 10 years ago. Building a new rig in a new house now, and want to achieve the same near-silent setup. The problem: I'm in Cyprus and it's already +35C (95F) outside and will get worse in July/Aug. Passive heat dissipation inside the gaming room is actually not what I want.

However, just outside I have an 11 meters (36') narrow water well for gardening. Ambient down there is stable around 12C (53F) through the year. I am thinking of a single closed loop going from the room straight down the well and back to the rig. In total it will be like 35 meters (38 yards) of tubing, CPU and GPU (1080Ti) waterblocks. The trick is that bulky garden pump is already submerged there, so I have to come up with a clever heat exchanger. I'm thinking of smth like this:



The tubing goes down into the well, spirals around the garden pump, maximising the cold water contact square, and then goes up to the rig.

Questions I'd like to get help with:
- Is it viable setup overall?
- Will standard DDC pump will be enough for 35 meters of tubing?
- What kind of non-metal tubing will be flexible enough to form the decent spiral in 20cm (8") tube and survive the 24/7 contact with water?
- It's unlikely but possible to go below freezing here in January, so I might get ice in the outdoor segment. Do you think I should be concerned?

Intermediary heat exchanger is an option, however I'd like to keep the system as simple as possible.

Cheers!

 

[Soulcatcher668]

Flexible copper pipe would be best for the heat-exchanger portion of the project. You could use PEX tubing for the run from exchanger to computer.

No way a regular DDC pump will work for runs like this, you are into pond pump territory here.

My worry is the amount of surface area that you have to dissipate the heat. How big is the reservoir at the bottom of the well?

 

[Blaylock]

Questions I'd like to get help with:
- Is it viable setup overall? I think this is a viable set-up and should serve you very well.
- Will standard DDC pump will be enough for 35 meters of tubing? I highly doubt a standard PC pump would be adequate. I would look into a fountain pump that can handle that much water. The volume of water will be based on the diameter of tubing you go with x the 35 meters in length. You'll want a flow rate around 3-4 liters per minute.
- What kind of non-metal tubing will be flexible enough to form the decent spiral in 20cm (8") tube and survive the 24/7 contact with water? Honestly your best material would be copper for a good heat exchange. Not sure why you would go non-metal.
- It's unlikely but possible to go below freezing here in January, so I might get ice in the outdoor segment. Do you think I should be concerned? Only if the well can freeze solid. Something you will need to be concerned about is condensation on your PC though. Cooling your rig below ambient temps will cause condensation to form. This needs to be addressed or you will have major problems with water on your board.

EDIT: Your quick Soulcatcher! Glad we agree on the course though.

 

[Soulcatcher668]

 

[Robert17]

Diggr posted up his project, ran copper underground and into his house. I can't find the thread, maybe it was a sticky at one time. Anyone with better search skills may find his posts from several years ago.

 

[Blaylock]

Do you mean this thread

or

this thread?

 

[wildmandnd]

You could use PEX tubing for the run from exchanger to computer.

Would it bend well to form a 20cm OD spiral? I've checked local shops for PVC tubes and they're all too rigid.

How big is the reservoir at the bottom of the well?

There is no reservoir down there as far as I understand. It's just a hole in the ground with 20cm plastic tube going to the ground water level and a garden pump hanging on the rope.

Not sure why you would go non-metal.

To prevent contamination of ground water and potential problems with neighbours/authorities.

Only if the well can freeze solid. Something you will need to be concerned about is condensation on your PC though.

No way, it's Cyprus after all )) Once in January car windshield water froze, thus the question. Condensation would be an issue, but I can solve it in many ways inside the house. Right now I'm not sure about the overall setup and water well part in particular.

 

[Blaylock]

OK. Copper is totally safe for underground water supplies and will not contaminate in any way.

 

[Robert17]

Do you mean this thread

or

this thread?

The first 'this thread'.

Copper makes algae and other miniscule plant life unhappy. Makes for a good algaecide all by itself. Using it for blocks and loops didn't happen by accident. So overall it's going to be a better conductor of heat, malleable, cheap (relatively), available, and anti-algae. What's not to like?

 

[Soulcatcher668]

Would it bend well to form a 20cm OD spiral?

The pex is for the run between the flexible copper and the computer. You do not want to use plastics for the heat exchanger parts because plastics does not conduct heat very well.

It does not sound like you have enough of a reservoir at the bottom of your well to dissapate the heat you are generating.

THIS might be a better idea.

This would be ground cooling as opposed to using ground water to cool.

 

[wildmandnd]

It does not sound like you have enough of a reservoir at the bottom of your well to dissapate the heat you are generating.

THIS might be a better idea.

This would be ground cooling as opposed to using ground water to cool.

You might be right, but there is no way to check it other than pulling out the pump and sneaking a waterproofed GoPro down there, which I don't have anyway...

That thread actually was an aha moment sparking my idea to use the well. I'm basically doing the same just with pre-existing hole in the ground.

 

[Thick8]

Are you sure that you are only 2 feet into the water table? I would think that would starve the garden pump.
But to answer your questions:
I'm in 15 feet of water with a 35' hole and have no problem dumping 800-1000 watts into it. As long as the bottom of the well pipe is perforated to allow water to flow instead of just getting hot and sitting in the bottom of the pipe, your spiral copper manifold should handle as much heat as mine.
Your DDC pump should work fine.
Use copper for the spiral and PEX for the run from your computer to the spiral.
Insulate the entire run.
Take a look at this thread as well. http://www.overclockers.com/forums/...ey-to-geothermal?highlight=journey+geothermal

 

[Thick8]

Waterproof Go-Pro? You need to think a little more basic. Push a garden hose down the hole 30' and blow in it. Do you hear bubbling? This is how I checked my water table. The fact that your hole has a 8" internal diameter is great. You could use 1/2" soft drawn copper to make your heat exchanger. Just wrap it around a piece of 4" electrical conduit pipe. You could wrap it down as deep as your water level is, and then back up so both ends are facing the top of the hole. This should make for a coil with a 7"(ish) diameter. If that would interfere with the pump then use a 6" diameter conduit and 3/8" tubing; as my tests have shown that low volume water is just as effective as high volume with a geothermal system like this. Plus the 3/8" tubing will provide more contact area for the water. There are TONS of videos showing how to do this on Youtube.