Noise from the RX360 res / leak

Right, it seems I have a leak. Crap.


Setup:

In January 2010 I build a new watercooling rig:
Loop 1: XSPC Dual Bay res -> Laing DDC-1 -> XSPC RX360 rad -> CPU Watercool Heatkiller r3 -> MIPS RAM Freezer 4 -> res
Loop 2: XSPC Dual Bay res -> Laing DDC-1 -> XSPC RX240 rad -> GPU AquagratiX HD5850 -> res

Note that all parts were new.

Coolant is 100% pure deminiralized water with a killcoil in the reservoir to take care of algae. No additives or fancy colours for me!

The system has been running smooth since (over 9 months). Bleeding has never been a problem and any air bubbles were always out of the system within a week. Water temps now average at 22.5°C. System temps vary between 20°C and 29°C.


Noise:

About a week ago, I noticed a strange noise coming from within the case *after* the computer was turned off. It is a quaint but fairly high-pitched squeel, almost like a bird chirping.

When the computer is just turned off, the sound is nearly continuesly: chirp-chirp-chirp... The frequence between the sounds decreases in time, until about 1 "chirp" every 2 minutes after an hour.

As far as I can tell, the noise is not present when the system is running.

The sound seems to come from the RX360 rad. If I press one of the fans on this rad, the sound plays continuesly regardless of how long the computer has been inactive. Note that this rad is the highest point in the system.

I could upload an mp3 with the sound if anybody cares.


Water level:

At the same time, I noticed that the water lever in the res is slowly lowering. I cannot tell the differene on a day-by-day basis, but after over week about 8 mm is gone from the res.

I immediately suspected a leak and inspected the inside of the case twice a day during the last 7 days, but have so far not found one single drop.


Help!

My money is on the RX360 leaking internally. What are your thoughts on this?

Now the tricky question: I ... ehm ... kind of promised my girlfriend I would not buy any new computer parts in 2010. Is there any way of repairing the RX360, plumber's concrete maybe? It would suck to go back to my old Black Ice 140 ...

do you see any puddles?

cut a piece of paper towel and place it at the barbs and such and see if any of them gets wet.
place one near the radiator and see if there's any wet spots first...

coolant levels may decrease as air bubbles are slowly being removed from the crevices of your loop... but if you don't see any puddles... hmm...

as for fixing radiator, i hear you can solder it shut if it's a small hole or something... but you still ahve to find the source of the leak...

could it be that you've punctured your rad by using long screws to mount the fan?

Nope: no puddles, no drops, no wetness, nothing. Barbs are dry as a bush. I left some blotting paper inside the case and no traces of drops here either.

I don't get it: if water level is dropping so fast, the water should go somewhere, right? The only thing I can imagine is, if there indeed is a leak, it is stagnating somehwere inside the radiator casing itself.

Normally I would think there is indeed just a large air bubble somewhere that is now dissipating. But after 9 months, the chance that there was still air in the system seems pretty small to me.

It could be that a screw punctured the rad 9 months ago and the gap expanded due to heat, although none of the screws I used are extraordinarily long.

well "leaking internally" still requires the water to go some place else.

A high pitched whine coming from a radiator is unlikely, from my experience. Are you sure it isn't the fan who's faulty? How is it hooked up, to a controller? Could be the capacitors on that controller that are slowly unloading. High pitched whines are usually capacitors leaking. Out of curiosity, try unplugging the power supply from the wall, wait a couple of seconds and then see if the high-pitched noise persists.

As kinghong1970 as said, the liquid level in the res goes down significantly during the first week of operation. I usually refill my loops after 2 weeks, a quick top-off. If you placed paper over all the joints and you see no water drips, no puddles on the case floor and no wetness anywhere, then it's unlikely there,s a leak.

Anyway, I find it unlikely that a radiator would make a whine. Especially a brand new one straight from the factory.

It definitely is not a fan: I only hear the noise when the computer is completely powered OFF. As in: power cable pulled out (having water disappear in my case makes me paranoid).

It also is not a capacitor: the sound is far more mechanical.

Neither is it a whine. It sounds like "squeek squeek squeek". Really, like a bird or cricket.

With "internal leak" I mean: I guess that the water in the rad does not actually flow freely in the black casing of the RX360? I always pictured that the case contains pipes. If this is correct, and one of the pipes is leaking, the water flows into the case of the rad?


Edit: I uploaded following video on youtube (yes, there is no image). Video starts at turning of the power - fast forward to about 2 mins to hear "the sound" in all its glory. Notice how the frequency decreases in time, to a slow chirp after about 7 mins. You may have to turn up the volume.

http://www.youtube.com/watch?v=MEM6jxxqHVo

it is possible to get a puncture that doesn't drip and does exactly what is happening... i think i'm going to use that video to help me goto sleep : ) so soothing...err sorry : *
;

OP, you could try switching back to your Black Ice 140 for a week and see if the water level still drops. If so, then you know it's probably not the rad (unless both of them are leaking), if it doesn't then at least you'll have confirmation something's wrong with the rad.

Had problems with my water levels dropping but having no leaks when I put together my wc rig too. Dropped about 5mm ever week so I re-did the rig, tighted up everything and the water level is steady now. But yeah it's a pain in the ass knowing water's disappearing from your system!

Well, does the noise continue after you unplug the PSU? If it does, then It could be a leak in the rad. Take your loop apart and empty the rad. Submerge the rad in water so that it is full of air with 1 or 2 feet of tubing on either barb coming out of the water. Cap one end off and blow in the other. If you see bubbles coming out then you have a leak.