Flow Rate Query

[Moptimus]

Originally Posted by zero_velocity

priming the pump would be one thing, but seeing as it is closed loop, there wont be any gravitational issues. it would simply be a sheer distance issue vs. head pressure of the pump.

Don't even bother. Everyone here kinda went one way or another, the butthurt was strong all round, and people almost went to the mattresses over it. I can't believe that it is still an issue, but it just goes to show that people can be stupid especially when they know think they are right.
See here if you still want to think that the pump head is an issue.

Anyway, enough off topic thread crap/e&wc circlejerk

OP, maybe less of the qdc will do you some good, they seem to be very restrictive. If you set it so you had them only at the in and out of the loop you could use something like this here on each block, that way you can disconnect your rad box, use spare qdc to drain the loop from the back of the case and then unplug tube from the dry items.

It would be less then ideal, but you might not get the same flow restriction issues, and you would not lose that much liquid each time.

The other thing to look at is how much change you actually go through with your loop, as if is not that much, then there is not that much reason for the qdcs.

[mrbean_phillip]

Originally Posted by zero_velocity

height is negligible. extra energy required to push water up is nullified by the lack of energy to required for it to fall

Hello Mate, you are 100% spot-on for a closed-loop system, don't worry about the comments from some of the 'experts' and WC-gurus on here...

This excludes Moptimus obviously, as he makes good use of his grey matter.

To the OP: I would say your problem wrt flow can attributed to the QDC's you are using, they are not that great in practice where flows are concerned.

I know a few guys on the WWW have done flow-testing on them, again, it also depends what pumps you are using - if not needed, get rid of them, and you should see 5-7lpm with that setup of yours.

[zero_velocity]

Originally Posted by mrbean_phillip

Hello Mate, you are 100% spot-on for a closed-loop system, don't worry about the comments from some of the 'experts' and WC-gurus on here...

This excludes Moptimus obviously, as he makes good use of his grey matter.

To the OP: I would say your problem wrt flow can attributed to the QDC's you are using, they are not that great in practice where flows are concerned.

I know a few guys on the WWW have done flow-testing on them, again, it also depends what pumps you are using - if not needed, get rid of them, and you should see 5-7lpm with that setup of yours.

would also be worth asking phatboy (on these forums). he is using a tonne of them on his build isnt he?

[mrbean_phillip]

Yep, I've used them a short while after they came out some years ago, and found them to be to restrictive, and bulky.

But, I would think 2.6lpm should suffice for most loops out there, with minimal gains to be had even to double the flow.

So, it's a bit of how much pratical benefit they have, if yes, keep them.


But, certainly something a bit off somewhere, as the cascade pumps should get up to around 6.5-8.0 lpm without to much fuss with the OP's loop.

[Creekin]

ops rad is external
hence the need for qdcs..
he removed one set and flow jumped from 2L - 2.5L

get rid of the other 2 sets and he should hit 3L no problemo

im building an external rad box atm and am trying to avoid using qdcs
as i have done before
http://forums.overclockers.com.au/sh...d.php?t=993135

[Formski]

Hi all,

As Creekin said, the QDCs seem to be the main problem here.

I've removed two sets (one set of VL4s and one of VL3s) and the flow rate is now about 3 Litres/minute . I'm thinking about leaving the other four sets in there as I need two sets for the external rad and the other two make life alot easier with the blocks.

I will add how important it is to bleed the loop properly - after removing the second QDC set the flow rate dropped down to about 1.5 - 1.8L/min and it was a bitch to track down and bleed the air pockets out.

I am wondering whether the QDC effect on flowrate is dependant on the individual QDC set though, especially after reading on the issues Koolance had last year with the springs. I found two of the male VL4s were not quite closing properly.

Either way looking good and the wife wants the dinner table back tonight so need to put it away at least for tomorrow...

Thanks again all for the help.

Formski

[Creekin]

Originally Posted by Creekin

get rid of the other 2 sets and he should hit 3L no problemo

Originally Posted by Formski

I've removed two sets (one set of VL4s and one of VL3s) and the flow rate is now about 3 Litres/minute .

i am teh winrar!!!!

Originally Posted by Formski

I found two of the male VL4s were not quite closing properly.

haha told ya!
glad u found them early, and the flow issue.

the boys over at XS claim 3.7L/min (1gal/min) is optimal but i find it too fast and noisy myself..
3L works for me

[Hood]

Originally Posted by Formski

4 sets of QDCs (2xVLN4s, 2xVL3s) - rad/res/GPUs/CPU

Originally Posted by Formski

I've removed two sets (one set of VL4s and one of VL3s) and the flow rate is now about 3 Litres/minute . I'm thinking about leaving the other four sets in there as I need two sets for the external rad and the other two make life alot easier with the blocks.

so which is it? you had 6 sets in originally? do you have a QDC fetish? wtf????

[mrbean_phillip]

Originally Posted by Hood

so which is it? you had 6 sets in originally? do you have a QDC fetish? wtf????

No, it seems he has a Creekin-fetish, if you ask me. But then, you didn't, so all good

@ OP: Glad you found the leaking QDC's, they can be a pain in the orifice, and one reason why I'm not using them. Of course, not to mention the flow-restriction they impose. But that's just meh, there will be a few good reasons to use them in the right build.

Good luck, hope your build works out well.

[Formski]

Originally Posted by Hood

so which is it? you had 6 sets in originally? do you have a QDC fetish? wtf????

Went through a QDC fetish - easily remove GPU/CPU/rad etc. without having to drain loop / get water everywhere etc. etc. Actually seeing a few builds in here (Phatboy69's for example) build made me think they were a good idea...starting to think a picture is worth a $1,000 worth of unneeded equipment.

Also it was written on a Friday hence the wrong number of sets - 6 in the beginning.

Formski

[Hood]

remind me not to put you in charge of heavy equipment or driving vehicles on a Friday!

can't remember where i read it, but some one made the comment you only need 1 QDC in the average loop, just put in the lowest part of the loop. when you want to drain it, just open the QDC fitting, and use another QDC mounted on the end of some tubing and lead it into a bucket. (total 3 fittings) Seemed like a good idea at the time, but it can be taken 1 step further by having a male QDC attached to a T fitting so it isnt actually part of the loop at all. to drain just hook up the female with some tubing to lead into the bucket.

Once the water is out, use compression fittings to take the loop apart, simple really.

[Formski]

Hmm...seems I spoke too soon...

I've now put everythiing in place and ensured the loop has been bled out. There is no pump bubbling noise (a little when started up only) and the rads are not making any swishing sound, yet flow rate has dropped back to 2L/min. This is the exact same setup that was recording 3 - 3.2L/min before it was moved over.

My suspicion was there was air stuck in the lop but I can't seem to find it and there doesn't appear to be any more than few minor bubbles. All fittings and tight and there is no kinked hosing. The case and the rads are all on the floor, so the height differential is the pump/rad which is near the top of the case (Lian Li X2000F) and the blocks.

I'm thinking maybe the VL4 QDCs that connect the rads to the rest of the loop are the problem, as they are the only fittings which have been hooked/unhooked. Anyone else have any further suggestions for looking at?

Formski

[Creekin]

how long have u bleed for?
i find i get up to full speed once the loop is full...the speed doesnt increase over the following days..
tried turning it off an on again? the qdcs i mean.. just to confirm they are all mating right....

also
PICS OR GTFO!!!!!!!!!!!!

[Formski]

Tried un and reconnecting QDCs - no real change.

Internal setup - res/pump not currently in case:


Bit better overview of the internals of the case:


And the mess that is the rads...:


Where the QDCs between the loop and rads are:


Not a pretty setup at all I know...

Formski

[Creekin]

1 pair of qdcs between the rads and mobo i can understand..
but the one on the gpu is derp and looks herpity derp!