Tubes turned yellow in a week

[marzipanius]

I'm running a fairly warm loop, at around 60C (140F), with clear DangerDen tubing made of PVC. Nothing but distilled water in the loop, and all components are copper. I understand that tubing becoming foggy is natural as plasticizers leak out when the plastics are heated up, but the yellowing is worrying me.

Looking into the plexiglas reservoir shows crystal clear water with no discoloring, and no film or coating inside the reservoir either. I keep my radiator mounted external to the case, so part of the tubing is exposed to indirect UV, and the other half of the tubing sits inside the case - no visible difference in discoloring between outside/inside, and since PVC is UV resistant I suppose this makes no difference what so ever.

I haven't detached any tubing yet to see if the yellowing is a film or if it's contained within the plastic itself. I did not do a "vinegar flush" the first time, but i did a several hours long normal distilled flush during my initial setup.

Any ideas?

 

[EarthDog]

60C is the water temp?!!!!!

What loop do you have and what is it cooling?

 

[marzipanius]

60C is the water temp?!!!!!

What loop do you have and what is it cooling?

It's cooling an undervolted HD7990 running 24/7. The GPU temperatures are 65C so I am estimating that the water itself sits at a slightly lower temperature - it might be lower than 60C as the tubing is only slightly warm to the touch, but PVC is a good heat insulator so it's hard for me to know without sticking a thermometer into the reservoir.

I'm running a Swiftech MCP35X pump at low-ish RPM, an EKWB 7990 SE block and a GT Stealth 120 radiator - a single 120MM radiator which I know is slightly underdimensioned for the wattage this graphics card puts out, but the GPU temperatures are still low and comfortable, far better than with air-cooling.

 

[EarthDog]

Yeah, you are pretty undradded for that card. Temps are better than air, but could be much better when you have enough radiator (3x120mm is what you should have).

Not sure about the reason for the discoloration... but a picture says a thousand words too...

 

[marzipanius]

Not sure about the reason for the discoloration... but a picture says a thousand words too...

Also worth to note is that the part of the tubing that sits over the barbs, unexposed to the distilled water, is still clear with no discoloring visible.

 

[sobe]

Probably just plasticiser.

 

[Contra]

dirty water...I say drain and refill...it was the powder in the lines probably

 

[RnRollie]

^^^this
probably impurities in the blocks/tubes caused it; clear/flush.. see what happens

Could be a bad batch of tubing - which is unlucky

Anyways, while the discolouring is ugly, it doesn't mean the tubes will fall apart tomorrow

Also, as a sidenote, if you can get your hands onto a 360 rad, do not hesitate !

 

[marzipanius]

I did run the loop a few initial hours before flushing it and refilling it, as mentioned in my first post, but maybe that was not enough for a cleaning?

I don't care the least about the appearance of the setup, only its functionality, but what should I do in case I fear part of this "gunk" has settled in the GPU block? Exactly what do I add to my water to dissolve it so that I can flush it out? Any chance it might initiate corrosion of the copper?

 

[GTXJackBauer]

Oh my. Do a complete tear down. Clean the pump, block, rad etc. Throw that tubing out and never use that kind of tubing again. Get some Primochill Advanced LRT tubing.

As for the water temp, 60c is alot. I would look at a 120.3 minimum and hang that in the back with some good radiator fans. Should bring down that water temp closer to your room temp. You could add the CPU to it as well if needed.

 

[marzipanius]

Oh my. Do a complete tear down. Clean the pump, block, rad etc. Throw that tubing out and never use that kind of tubing again. Get some Primochill Advanced LRT tubing.

As for the water temp, 60c is alot. I would look at a 120.3 minimum and hang that in the back with some good radiator fans. Should bring down that water temp closer to your room temp. You could add the CPU to it as well if needed.

PrimoChill is also PVC-based. I don't see how this brand would be a guarantee of not emitting the same gunk. And what do you recommend for cleaning the loop? I can't open the block up, nor the pump, as that would void warranties, so what can I add to the water to dissolve this plasticizer?

 

[GTXJackBauer]

PrimoChill is also PVC-based. I don't see how this brand would be a guarantee of not emitting the same gunk. And what do you recommend for cleaning the loop? I can't open the block up, nor the pump, as that would void warranties, so what can I add to the water to dissolve this plasticizer?

Use some warm distilled water and wipe your pump and block, etc for any possible build up. If you don't want to void your warranty that is fine. Just run the pump, block and reservoir outside of the case and keep reflushing it with new distilled water each time for a few hours. Not sure if thats going to do much without opening them.

Can I ask what did you use as a biocide with the distilled water?

The new line of PrimoChills Advanced LRT tubing is plasticizer free. Most of us are using PrimoChill Advanced for at least 6 months with no issues. I have used clear and colored with no issues whatsoever. It is the choice of tubing whichever forum you go to. Its the best tubing out there. You can take my word for it. Just search for some reviews.

 

[marzipanius]

Use some warm distilled water and wipe your pump and block, etc for any possible build up. If you don't want to void your warranty that is fine. Just run the pump, block and reservoir outside of the case and keep reflushing it with new distilled water each time for a few hours. Not sure if thats going to do much without opening them.

Can I ask what did you use as a biocide with the distilled water?

The new line of PrimoChills Advanced LRT tubing is plasticizer free. Most of us are using PrimoChill Advanced for at least 6 months with no issues. I have used clear and colored with no issues whatsoever. It is the choice of tubing whichever forum you go to. Its the best tubing out there. You can take my word for it. Just search for some reviews.

No external biocide used. Nothing is growing in that loop. PVC secretes formaldehyde when heated up - something no computer parts vendor seems to know/care about - so the water in the loop is on its own filled with a very potent biocide (and unfortunately a strong carcinogenic to boot...)

Is there really nothing that can be added to the water during a flushing to help dissolve this? Should it actually be plasticizer - I still haven't cut a piece of tubing off to see if there's actual film/coating inside it. I did read another report from someone with yellowed tubing that had no film what-so-ever built up inside, so I'm still uncertain as to what the yellowing is.

 

[GTXJackBauer]

Its could possibly be plasticizer and growth. We never advise to run a loop without a biocide. I would take apart that block and pump undoubtedly. You won't know if there is any growth till you take them apart since the plasticizer from what it appears in the picture is in the way.

Plus you're way underrated.

Please take the time and read up our water cooling stickies to get a better understanding.

 

[marzipanius]

Its could possibly be plasticizer and growth. We never advise to run a loop without a biocide. I would take apart that block and pump undoubtedly. You won't know if there is any growth till you take them apart since the plasticizer from what it appears in the picture is in the way.

Plus you're way underrated.

Please take the time and read up our water cooling stickies to get a better understanding.

There's no growth anywhere in the loop; too much formalin present for any bacteria or fungi (that may or may not have gotten in) to even stand a snowball's chance in hell to survive. I know the radiator is underdimensioned for this kind of thermal dissipation, but it's not an acute problem.

So... what about dissolving agents for the possible plasticizer? Anything you can recommend? How about acetic acid (vinegar), does that dissolve it?

 

[S_I_N]

Primochill advanced LRT here as well the stuff is Legend.................wait for it.............ary

Over a year here with it and NO ISSUES at all.

 

[m0r7if3r]

I've seen plenty of loops come through with growth, I doubt anything is going to be doing much leeching at ~10C over ambient or less, or it would be doing it on hot days in the summer.

 

[sobe]

Well, PrimoFlex went through their own plasticiser failure with their last gen of tubing, the Advanced LRT stuff would be good, or if you want to save just a little bit on tubing, grab some XSPC HighFlex which does not have any plasticiser issues, and didn't suffer when the Pro LRT was out.

 

[Thekamikazepr]

looks like p[lasticer happened to me as well. Do you have a coil or biocide?

 

[marzipanius]

looks like p[lasticer happened to me as well. Do you have a coil or biocide?

No coil or biocide added to the water, but it's not bacterial/fungal/algal growth in there. I'll obtain some tubing reported to be plasticizer free, and try to flush residue out of the pump and block - any advice on what substance I can use in the water to dissolve plasticizer without harming the copper or acrylic reservoir?