Slow leak/evaporation

So since I put together my new loop (link to build log in sig), I've noticed the water-level dropping at an abnormally quick rate. It visibly drops in level every week or so, maybe about .5cm in a couple of weeks. I've never had water permeate through tubing so quickly, so I'm assuming something else is afoot. There is NO moisture around any of the barbs (either at the base where they enter the block/pump/rad or where they meet the tubing), so it's not a quick leak. There are also no more bubbles, the system is fully bled and shaking does not introduce any more.

My guesses would be an extremely slow leak or perhaps the facilitation of evaporation through the four Koolance 90° fittings I have on my radiators. Has anyone had any experience with a slow leak out of the fittings in question?

Any other ideas/things to check?

look for something dripping out of/onto your pump, pump might be helping it evap faster because it's warm

m0r7if3r said:

look for something dripping out of/onto your pump, pump might be helping it evap faster because it's warm

Click to expand...

As I said earlier, there's no visible leaks or water/moisture anywhere on or around any components. Perhaps a small opening somewhere that facilitates evaporation, but I just don't know where. There's no visible or tangible water anywhere, though.

Have you checked the rad for leaks? Maybe one near a screw?

Yep, no leaks anywhere.

Started running FAH again (CPU and GPU), left the computer on overnight and the water-level dropped about 3mm overnight

I'm convinced it's evaporation now... but from where? That's the question.

Only things I could think of are the quick-disconnects I'm using or the 90° Koolance fittings being loosely-sealed enough for evaporation to occur rapidly, but for water to not leak out.

Another idea would be a leak in the res? The sides of the res above the water level are almost consistently covered by condensation (on the inside). Like in this picture:



Look above the water level in the res and see how it is slightly foggy. Perhaps it's just evaporating through the top of the reservoir (either around the side or the barb fitting?)

On a side note, any idea why the tubing in the res changed color? I assume it's normal for tubing being submerged, but at the same time I've never seen a piece of tubing fog up so quickly. The tubing is 7/16"x5/8" MasterKleer from McMaster-Carr. It turned almost entirely opaque in about a week.

IIRC, masterkleer fogs pretty quick (ironically lol)

m0r7if3r said:

IIRC, masterkleer fogs pretty quick (ironically lol)

Click to expand...

True, I have been using it for years and it does fog quick but I have never had an issue with evaporating through it so I don't think that is your problem. I notice you don't have any type of clamps on the tubing so I would bet you are getting slow little leaks around that quick connect above the res. I once had a leak at a radiator barb that leaked out so slow it dried before moving from the barb spot. Try clamping the tubing then see how it does.

Your Pump Runs Hot.

Snake, triple check your rads for a tiny leak. And doing that, you would be better off powering the pump with a separate psu while the rest of the computer is shut down. That's because the heated water in the loop makes evaporation go faster with the computer powered up. The reasin I am saying this is that I faced a situation similar to yours about a year or so ago. My loop was slowly losing water and at a faster rate than it had previously. I took the sides off my U2-UFO case and didn't see any obvious leaks the first time I went looking for the leak. Then after it continued for a few more months I decided to tear apart the loop and clean things anyways. When I stated looking around inside, I noticed a deposit on the motor of my Iwaki, which was sitting right under my heater core rad, but no obvious leak. I then powered up the pump after leeting the loop cool down to room temp and let it run a while and after giving it an hour or 2 run, started checking all fittings andcomponents with a kleenex and my fingers and while checking the bottom of the heater core, found the corner over the pump damp. After looking at it closer, one of the tubes was slightly abraded and had a hairline leak in it next to where some all thread rod went through to hold the fans and shroud on. After changing the heater core for a new one, my water disappearing problems went away.

So anyways, check things over very closely and with the loop as cool as possible.