Z's "Other Room" Water Cooling Loop Build Thread

[Zarathustra[H]]

So,

For some time now (think years, if not a decade) I've been toying with the "what if" idea of, what if I just built a large enough water loop that I could relegate all fan noise to another room, and finally compute in actual silence.

When I got my Threadripper which outputs a good amount of heat, I thought about this more. And then once I picked up my XTX 6900xt EKWB edition which I overclocked such that it put out 430w for just the GPU, I became even more interested in this concept. Replacing the 6900xt with a 4090 has not improved things.

Not only can I get rid of that pesky fan and pump noise, but I can also sit in a room that is not stupidly hot in the summer due to having a 1000+w combined power output.

This build will be documented here in this thread AND in thefpsreview forums. The build will progress slowly, so don't expect frequent updates. A little here, a little there should do it. I may be done in a few months, or it may take a couple of years. Not sure yet. It depends on how much time I have and what the budget looks like over time.


I'm usually someone who thinks about my projects for a long time before I execute, and the planning phase is usually much longer for a big project, so to say I have given this some thought is a real understatement.

The high level plan:
- Build a water loop that has only the blocks in my office. All noise and heat emitting parts of the loop are in a different room.
- This "different room" will be my "server closet" which is about 50 ft away on the other side of the finished basement.
- Luckily the finished basement has drop ceiling panels, so running tubing up there should be relatively easy.
- Cooling may just be high speed fans and radiators, but if I am feeling like it when the time comes it may even be water chiller based.
- Loop will be a "two loop" solution.
- One long loop (pumped from reservoir in other room to office, pass through CPU and GPU block, and return back to other room back into reservoir)
- One short loop (pumped from reservoir to radiator/chiller and back to reservoir)



Slightly more details:

- I was originally going to use a soft Tygon-like tubing, but after discussing it in this thread I decided to go with PEX. Further research made me land more specifically on PEX-A, as I'm pretty sure the extended length of this loop will challenge my pump capacity, and PEX A has less flow restriction as fittings stretch the PEX out, instead of fit inside it, like PEX-B does.

- The plan is to use dual D5's for the big loop, and a single D5 for the short loop. I will be using PWM controlled D5 pumps, as I don't want them going full blast at all times. This means I'll have to run a PWM wire from my office to the remote room to control the pumps. This may or may not wind up working well. After discussing it here, I have decided to send the PWM signal either via a CAT-6a or better cable, or a coaxial cable, and hopefully the signal remains intact the 50+ft it will take to get there. In order to keep a shared ground, I am going to power those two pumps from my PC's power supply. I'll probably use normal solid electrical wire to carry the +12v and ground from my PC to the other room, and hope the voltage doesn't drop too much. Worse comes to worse, I may be able to use an ebay sourced cheap DC-DC boost converter to pull the voltage back up to 12v on the other end. Time will tell if that will be needed.

- I'm hoping to wind up using two water chillers. One small, quiet and power sipping one for idle or near idle power loads, and a second big, powerful, and potentially loud and power wasting one to supplement at high loads. I had been looking at the Hailea chillers they had on Performance PC's, but they have been out of stock forever now, and it seems unlikely they will come back into stock. I'll have to do more research to figure out which to use, but there seem to be a bunch of different models on Amazon to choose from. This may wind up being too much though, and I may fall back on just "lots of radiators and fans" instead. Time will tell.

- With the water chiller, I'd probably wind up running slightly sub-ambient. You know, below ambient, but above the dew-point, to avoid condensation. This adds some design challenges. Firstly, I'm going to want to insulate the PEX so I don't suck up too much ambient heat in transit.

- Secondly, compressors don't like rapidly switching off and on again, as this can damage the compressor. Most of them have electroic controls for this, that refuse to turn back on until a certain amount of time has passed (usually 3min?) since last shutoff. I want the system to be able to control the water temperature to within ~1C. This means that I need to have a large enough amount of water that even if the PC is dumping heat into it at full load (~900w?) I won't raise the average temperature of the coolant more than 1C in 3 minutes when the chiller is off.

- Initial heat transfer calculations suggest I'll need about 10gallons of coolant in order to limit it to a rise of 1C in 3 min with a load of 900w, but it's not quite as bad as that. Firstly, there'd be two chillers. Presumably if the big one turns off, the small one will keep running. Assuming the small one keeps removing about 250w of heat even when the big one turns off, that means I only have to deal with 650W, not 900W. This means I've now reduced my coolant needs to about 7.4 gallons. Add to that, the 900W is an absolute worst case power load for my system, which probably won't happen very often, even in an intense gaming or rendering session.

- Still, this means I am going to need a large reservoir. I am considering using a 6.5 Gallon wide mouth glass carboy usually sold for home brewing purposes. Using a specialty drill bit, I'd drill holes in the bottom and install bulkhead fittings to allow me to hook up tubing. The 6.5 gallons may not be quite enough, but there will also be just over 2 gallons in the tubing at any given time (according to my calculations) so it should be sufficient.

- I don't want to absorb too much heat into the glass carboy, so it will have to be insulated. I haven't measured things yet, but I think it should fit inside a small 20 gallon Brute professional trash bin. I'll throw together some sort of support structure (probably criss-crossed 2x4 scrap pieces) in the bottom, then put the carboy in on top and insulate under and around it using spray insulation foam. I'd then also glue some insulation to the lid, as well as cut holes in the bottom and the top for tubing to go through.


So, this is pretty much the plan thus far. I'm pretty sure that as I start working on it, reality will set in, and the plan will change several times, but at least this expresses where I am trying to go with it. I will post pictures and progress as I go along, but as I mentioned, it will be slow moving.

 

[toast0]

This sounds like a fun time, but did you consider just running a long video cable and some sort of usb extender from the other room?

 

[NightReaver]

Well, glad you settled on the PEX. Actually forgot about that thread. As for the rest...uh...wow. That's a project lol. My vote is still for simply put the PC in the basement and use extended cable to operate it, but hey, run wild with it

 

[Zarathustra[H]]

This sounds like a fun time, but did you consider just running a long video cable and some sort of usb extender from the other room?

I did think about that, and tried it a few years ago, but I had connectivity problems with long monitor cables, and USB extenders.

Maybe modern Thunderbolt based docks with optical extensions would work better than the last time I tried things, but I also kind of like the idea of having the computer right next to me.

Either way, one of the appealing aspects of this project is to get to do some old fashioned DIY water cooling on a large scale

 

[Zarathustra[H]]

As some wise person somewhere at some point said, the key to getting done is getting started, and in this post we are getting started. We have gone from the planning stage into the early execution stage.

So I did some additional research on PEX tubes.

As mentioned above, I had settled on PEX-A, as with PEX-B fittings go inside the diameter of the tube and can obstruct flow. For this project flow is going to be of great importance, so I wanted to do as little as possible to obstruct it.

Further research led me to this PEX specification page.

Lots of good information there that was helpful, including OD and ID ranges, weight of the tubing per linear foot, etc. etc.

My plan was to lay the tubing above the drop ceiling on top of the tiles at first, after which I will attach foam insulation around it, and then as a last step, screw it to the wood ceiling beams. I wanted to make sure the PEX in and of itself wasn't going to be too heavy for the first step, and damage the drop ceiling supports.

Turns out the weight comes nowhere near the level that would be damaging, so I am not worried.

What I also found on this page was the pressure drop table for various PEX tubing sizes:

I don't know if dual D5's will allow me to get there, but I am hoping to hit above 1GPM. According to this table 100ft (50 ft each way) of tubing length. I went ahead with the 3/4" PEX, as a 0.34psi (0.782 ft of head) seemed good enough, considering dual D5's put out 12.9ft of head according to the specs I have found.

I originally wanted to play it safe and go for uncolored PEX, as I didn't want to risk anyhting leaching out into the fluid. Remember, drinking water passes through the tube once, but coolant will circulate for a very long time, so there is greater chance of leaching, but I found an amazing deal on a kit that contained two rolls of PEX (red and blue) a good tubing cutter, and all the the compression rings for fittings I could ever want, so I went for it.
Turns out they are only colored on the outside anyway (though the light bleeding through makes the whole thing look colored)

I had never worked with PEX before. Turns out it is pretty stiff stuff, and it has a lot of memory coming off the roll. This could in part be due to working in New England Winter temperatures. I had to keep stopping my pull, and bending the tube back against the roll to straighten it.

You have to be careful when you do this, because bend too much and you can kink it.

I cut this piece out because of an inadvertent kink:

Turns out you don't necessarily have to do that. At least not with PEX-A. (the others you may have to).

With PEX-A you can heat it up with a hair dryer or heat gun, and the PEX material tends to want to return to its original shape. A hard dryer can take a while and be a pain in the ass. A heat gun can quickly go form not enough heat to too much, but it's better than having to cut out the section.

After that I just kind of had to pull it through the ceiling, tile by tile.

(Note the tape covering the end, so I don't get crap inside the tube)

And here we are, both tubes near their final destination.

(The electrical closet is attached to my office, and my desk is a few feet from that door.)


Next steps are too figure out how I am going to route these to my desktop. I was going to try to come through from the electrical closet, but I don't think that is going to work, so my current plan is to cut a hole in the ceiling tile above my desk, and run a couple of extra large cable raceways down from the ceiling to where my desktop is.

I am going to do 90 degree bends on both sides up in the ceiling before the tube goes straight down. (I hope too much air doesn't get caught in the top corners). Then close to the computer and close to the reservoir I am going to install hose barb fittings in the PEX to transition to more common water cooling tubing before entering the PC.

I have ordered some XXL cable raceways from Electriduct. Their largest size is 2x3". The OD of the insulation that is going to wrap around the PEX should be 1.98", so they should fit one per raceway.

Once I have the raceways figured out its time to buy lots of pipe insulation at Home Depot and start installing it around the pipes, and then install the hangers to the wood ceiling.

Most PEX hangers are designed to go around bare pipe, so I am going to have to do something else. I may use galvanized hanger strap around the outer dimension of the foam insulation and use that to support it. I am concerned that once th epipes are filled with coolant, it will be too heavy for the drop ceiling, so hanging will be necessary.


I'm also going to have to buy a PEX-A pipe expander in order to install the 90 degree bends. I'm probably going to use a manual one, as the electric ones are pretty damn expensive, and I am only going to be doing 12 joints.

We have:
Hose barb adapter near pump (one joint)
Tubing from pump up to ceiling -> 90 degree bend (one joint)
Tubing from 90 degree bend to ceiling tubing (one joint)
Ceiling tubing to 90 degree bend (one joint)
90 degree bend to tubing down to PC (one joint)
Down tubing to hose barb (one joint)

So that is 6 joints for each run, and there are two runs, so 12 in total.

I can use the manual stretcher for just 12 joints I think. No need to spend $600 on a battery powered tool...

 

[NightReaver]

Rolls? Yeah. Sounds cool at first but a total mess to work with. The straight pieces are what you always want unless dropping it in a trench or something.

Almost made that mistake when buying it for the 1st time

 

[rhkcommander959]

Awesome project!

Pex is great, best to use the rolls in the summer when the heat can help it uncoil, I prefer straight sticks for this reason. Or you can hook it up to a hot water line and blast away at full temperature...

Like you discovered, the color is only on the exterior. White translucent is the base color, some manufacturers stopped coloring the whole tube and instead just wrote in red or blue too.

P-Tape can strap the pipes after insulation easily. 3/4 pex filled isn't that heavy, I forget how many feet equals a gallon but its a lot. P tape and some phillips screws every 2 feet or so, good to go. The expander tool can be rented, worth every penny IMO but the manual is fine too.

I'm thinking about just burying a coil for geothermal myself, ground temp year round would be great but would go subambient. I worked with TECs for years though so I'd be fine there.

Is your server closet air conditioned? If not, why not just go into a crawl space or something closer? Food for thought. D5 are great, otherwise there are some industrial/aquarium pumps that could do.

 

[Zarathustra[H]]

Rolls? Yeah. Sounds cool at first but a total mess to work with. The straight pieces are what you always want unless dropping it in a trench or something.

Almost made that mistake when buying it for the 1st time

Yeah, I bet straight pieces would have been easier to work with, but I also bet you can't buy 100ft long straight pieces

So I would ahve had to join them a few times in the ceiling, which sounds like a leak risk.

I like that it is one solid piece of PEX tubing all the way!

 

[Zarathustra[H]]

Awesome project!

Thank you!

P-Tape can strap the pipes after insulation easily. 3/4 pex filled isn't that heavy, I forget how many feet equals a gallon but its a lot. P tape and some phillips screws every 2 feet or so, good to go. The expander tool can be rented, worth every penny IMO but the manual is fine too.

Interesting. I may look into renting the tool.

Can you expand on the P-Tape thing? I googled but I can't find anyhting. I bet its some sort of abbreviation or something.

 

[NightReaver]

So I would ahve had to join them a few times in the ceiling, which sounds like a leak risk.

Sure. Technically it is. But it really isn't especially with PEX A...assuming you're doing it right. If you end up doing any plumbing work with PEX again in the future, the 10' sticks are really, really nice to work with.

 

[rhkcommander959]

Thank you!



Interesting. I may look into renting the tool.

Can you expand on the P-Tape thing? I googled but I can't find anyhting. I bet its some sort of abbreviation or something.

Short for plumbers tape, but you're more likely to see it called "pipe hanger strap" because ptfe tape is being called plumbers tape now too... You can get galvanized steel or plastic, honestly plastic is good enough for your project too and very VERY easy to work with. Tin snips will cut both but steel is way overkill for pex. A single sheetrock screw or gold interior is enough through the strap, just don't overdrive through the plastic, no need for more screws but you do you.

Pex expansion done right won't leak. I probably ran miles of pex lol. If you ever have a slow leak, hit the joint with light heat to shrink it more but really, it shouldn't leak unless you drive a sheetrock screw through it lol. Or way WAY overstretch it, which is easier IMHO with manual tools, electric tools I just count it out per size. Also if the manual tool doesn't rotate the head, give it a slight turn between stretches for a more uniform stretch.

 

[Zarathustra[H]]

Short for plumbers tape, but you're more likely to see it called "pipe hanger strap" because ptfe tape is being called plumbers tape now too... You can get galvanized steel or plastic, honestly plastic is good enough for your project too and very VERY easy to work with. Tin snips will cut both but steel is way overkill for pex. A single sheetrock screw or gold interior is enough through the strap, just don't overdrive through the plastic, no need for more screws but you do you.

Pex expansion done right won't leak. I probably ran miles of pex lol. If you ever have a slow leak, hit the joint with light heat to shrink it more but really, it shouldn't leak unless you drive a sheetrock screw through it lol. Or way WAY overstretch it, which is easier IMHO with manual tools, electric tools I just count it out per size. Also if the manual tool doesn't rotate the head, give it a slight turn between stretches for a more uniform stretch.

Ah, nice. I bought a 100ft roll of galvanized strap. I did see the plastic stuff there, and I considered it as I through ti would be easier to work with, but I wondered if it would be sufficient. Having given it some thought, maybe I'll return the galvanized stuff and go for the plastic.

Where have you seen pex expanders for rent. I have done some googling, but come up short. It's not on Home Depots list for instance, but maybe it is something they have in store if you ask and not on the website?

 

[rhkcommander959]

Our HD would rent them, ask if they have a Milwaukee ProPEX Expander. I didn't see much for plumbing tool rentals on their site, but it might be regional or they may have quit doing it too.

Galv steel strapping is fine, just overkill. Can be nice and sharp too.

 

[Zarathustra[H]]

Our HD would rent them, ask if they have a Milwaukee ProPEX Expander. I didn't see much for plumbing tool rentals on their site, but it might be regional or they may have quit doing it too.

Thanks. I wonder if this is a Massachusetts thing. Here you arent supposed to do your own plumbing by state law. You are supposed to hire a licensed plumber. Seems union/protectionist in nature. :/

That said, they do sell all the piping, cement, faucets etc. etc,

I'm going to go in and ask in person and see what they say.

Galv steel strapping is fine, just overkill. Can be nice and sharp too.

Yeah, in retrospect after buying it, that is what I am concerned about. Either cutting myself, or something else I do't want cut. I'm probably going to return it and pick up some of the plastic stuff.

 

[Zarathustra[H]]

Hmm.

The plan was going to be to work on the raceways in my office next, so I could more and cut the PEX to its exact length, and do the 90 degree joints at the edges of the ceiling, but the raceway accessories I want are backordered until the end of May. :/

This is going to necessitate shifting gears. I wanted to hook up the tubing and flow test everything before I started building the reservoir, but maybe that order of things is going to have to change.

 

[rhkcommander959]

Thanks. I wonder if this is a Massachusetts thing. Here you arent supposed to do your own plumbing by state law. You are supposed to hire a licensed plumber. Seems union/protectionist in nature. :/

Not without a permit, but surely if you get a permit and do it to code you should be OKp
I was in the trade for a while, but just replumbed my whole house on both DWV (waste pipes) and potable hot and cold PEX, inspectors were happy.

The plastic hanger strapping is plenty. When you test DWV for instance you plug the main drain before it goes to the sewer system, and plug any other drains, and fill water up to the roof through the vents. My 3 inch ABS pipes held fine with plastic straps and didn't budge with all of that weight, so 3/4 pex won't even bother the straps. I wouldn't bother with the steel strapping until stepping up to cast iron waste pipes really.

Not trying to derail your thread, I look forward to your progress