watercooling flow issue

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kaigame

Weaksauce
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Hi all, have a bit of an issue, let me give you the basic spec

Asus Strix X470F-F Motherbord with EK Monoblock
GTX980TI with EK Waterblock
2x 480mm Radiators
Alphacool Eisfach reservoir with VPP755 D5(ish) pump

Order Reservoir -> CPU - > 480mm rad -> GPU -> 480mm rad -> Filter -> Reservoir

I've just replaced my old trusty DDC pump with this one, i don't think there is anything wrong with the vpp755 pump, but the flow rate is so low my flow indicator(between the GPU and 2nd rad) doesn't spin.

The DDC pump would spin even at the lowest speeds, the vpp755 won't spin at maximum, i can hear the impeller spinning and if i block the flter(easy clean), and unblock i see flow.
**Build up of pressure causes temporary flow, lasts a second**

Any tips or suggestions, i've sent an email to the place i bought it from.
 
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That seems like it might be a lot of flow restriction for a single D5 type pump. D5s have lower head pressure than DDCs, so it might not be the best choice for your loop. That being said, have you verified the RPM at which the pump is running?
 
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BrotherMichigan said:
That seems like it might be a lot of flow restriction for a single D5 type pump. D5's have lower head pressure than DDC's, so it might not be the best choice for your loop. That being said, have you verified the RPM at which the pump is running?
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It's reporting as 4500rpm from BIOS, i have no other means of checking it. That would be a shame though, it's so much quieter :(
 
That's not too much restriction. I run the same number of components with my D5 and get about 150l/hr of flow with the pump at 3000rpm.

I would suspect your flow indicator before anything else. Those spinnywhimmydiddly type indicators are notorious for binding up and no longer spinning.

How are your temps? If you're actually getting no flow, it'll be very apparent in component temperature under load.
 
VanGoghComplex said:
That's not too much restriction. I run the same number of components with my D5 and get about 150l/hr of flow with the pump at 3000rpm.

I would suspect your flow indicator before anything else. Those spinnywhimmydiddly type indicators are notorious for binding up and no longer spinning.

How are your temps? If you're actually getting no flow, it'll be very apparent in component temperature under load.
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The flow indicator is flawless, it worked just before i changed pumps, there is also a filter(with a window), and i can see barely any flow coming through it as there are always a few bubbles in it.

Temps are ok idle, but as soon as i push things it's getting a little high. More than anything, i can see the lack of liquid flow in the system, it's not even equivalent to the DDC pump at it's minimum. But it's good to know that it might not be the pump thats inadequate.
 
What kind of filter do you use? If there really is low flow then you have a blockage somewhere, I'd look at the filter first (never used a filter personally in a wc loop), then start taking your blocks apart for a clean.
 
Killerxp100 said:
What kind of filter do you use? If there really is low flow then you have a blockage somewhere, I'd look at the filter first (never used a filter personally in a wc loop), then start taking your blocks apart for a clean.
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It's not the filter, at lest i'm sure of that. I've dismantled the PC, i have 2 screws on my monoblock with mashed heads, can't unscrew them, really annoying!!! might have to drill them out.....

Going to clean out the whole thing, liquid and tubing change. Will take me a while due to the issue with the monoblock.

Thanks for all the tips, i'll let you know once it's all done.
 
So, small update, i went to B&Q, got some screw extractors, and with a lot of drilling and sweat got the monoblock apart, there's a lot of gunk in there.
I'm going to switch from UV blue to clear liquid in my loop, so everything is getting a clean, doing the radiators tomorrow, and hopefully by the end of the week should have everything back together again.

I have a small question prior to assembly though, hoping someone can give me a tip, the rads i'm using Alphacool 480mm (ST60 i think) has a single port on one side, a bleed port i think, the question is can this be used as a outlet, or inlet? as in can i have water going in on one side of the rad and out of the other? will shorten the amount of tubing i need.
 
kaigame said:
So, small update, i went to B&Q, got some screw extractors, and with a lot of drilling and sweat got the monoblock apart, there's a lot of gunk in there.
I'm going to switch from UV blue to clear liquid in my loop, so everything is getting a clean, doing the radiators tomorrow, and hopefully by the end of the week should have everything back together again.

I have a small question prior to assembly though, hoping someone can give me a tip, the rads i'm using Alphacool 480mm (ST60 i think) has a single port on one side, a bleed port i think, the question is can this be used as a outlet, or inlet? as in can i have water going in on one side of the rad and out of the other? will shorten the amount of tubing i need.
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If you combined both the ports on the tubing side this could work, but otherwise it won't - you'll only get flow through half your radiator.

The coolant path inside that rad is shaped like a "U", if you can visualize it. It goes in on one side, passes through that side's channels, switches to the other side at the end tank, and returns through the other side channels, and leaves through the other side.

Does that make sense?
 
VanGoghComplex said:
If you combined both the ports on the tubing side this could work, but otherwise it won't - you'll only get flow through half your radiator.

The coolant path inside that rad is shaped like a "U", if you can visualize it. It goes in on one side, passes through that side's channels, switches to the other side at the end tank, and returns through the other side channels, and leaves through the other side.

Does that make sense?
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Unfortunately it does :)

I thought it was worth an ask though haha!
 
kaigame said:
Unfortunately it does :)

I thought it was worth an ask though haha!
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I know you're probably not interested in buying another rad, but Alphacool makes them in the configuration you want - they're called cross-flow radiators.
 
XSPC and Hardware Labs make crossflow or x-flow radiators for some of their lines too, though the performance can sometimes suffer a bit.
 
BrotherMichigan said:
XSPC and Hardware Labs make crossflow or x-flow radiators for some of their lines too, though the performance can sometimes suffer a bit.
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Got a source on that? I'd be curious to see it. Ostensibly cross flow rads would work just as well - water moves through it at half the speed through twice the channels (and thus half the flow restriction.)
 
VanGoghComplex said:
I know you're probably not interested in buying another rad, but Alphacool makes them in the configuration you want - they're called cross-flow radiators.
Click to expand...

It's a thought, but i'm loathed to spend any more than i need to at this time, i got the two 480 rads for £40, so i'll make do :)
 
VanGoghComplex said:
Got a source on that? I'd be curious to see it. Ostensibly cross flow rads would work just as well - water moves through it at half the speed through twice the channels (and thus half the flow restriction.)
Click to expand...

Sure thing! Here's a review of the Hardware Labs Nemesis 360 GTS X-Flow from XtremeRigs that also includes data for the "normal" 360 GTS: https://www.xtremerigs.net/2015/09/19/hwlabs-nemesis-360-gts-x-flow-360mm-radiator-review/

It's not a huge difference, but the performance is pretty consistently lower than the normal 360 GTS. The same result is echoed in their test of the 280 GTS X-Flow, too. Honestly, the only thing I can think of is that maybe the plenum chamber design has some effect and the flow is not even across all of the tubes. If that's the case, this very well may be an issue unique to HWLabs, but these are the results I was thinking of in my above post. *shrugs*

*EDIT* VanGoghComplex Turns out the X-Flow radiators are single row, single pass whereas the U-Flow radiators are dual row, dual pass. Guess that explains that.
 
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OK, i must have had a lot of crap in that loop.

I finally put everything back together again, the Alphacool Bay Reservoir is a little awkward to get going, but my flow rates are now higher than what i've seen with with the old DDC pump, which is awesome!!!!

Cleaned out the rads, scrubbed the fittings, dismantled the blocks, new tubing and clear liquid and everything is running smoothly.

I ditched the filter, although it was a handy drain port also, draining this thing is going to be fun. I'll get a proper tube reservoir next methinks. Just have to plug all the fans and cables, and switches, etc in now, but all is working perfectly.

I can finally see some benefit to having a D5 pump :D

Thanks for the advice.
 
So, another update, The pump decided to stop working on me..... already!! i got up this morning, turned the machine on, and zero flow whatsoever!! i can hear the pump trying to start and failing.

I know the loop is clean and this is the last straw!! This Alphacool pump and bay Reservoir is a piece of crap!! Going to switch to a normal D5 pump and tube reservoir hopefully this weekend.
 
maybe a stupid question, how dense is your fluid? I recommending flushing about 25% of fluid, and adding distilled water.
 
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cyklondx said:
maybe a stupid question, how dense is your fluid? I recommending flushing about 25% of fluid, and adding distilled water.
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Not sure why that would be a silly question, i'm using Mayhem X1 clear coolant, seems liquidy enough. I was getting really good flow rates for a week and a bit an all of a sudden, zero!

To add to this, i didn't have much chance to really troubleshoot this before i left for work at 5:30am, so i'll take a look when i get back (hopefully with a replacement D5 pump+reservoir).
 
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So this is a pre-mix? If you have plenty left, i'd consider adding distilled water anyway - see if that helps. If not I'd be keen to state you have a big bubble stuck in your pump (maybe try rotating it a lil).

other than that I always do my setups in pull push
(I use mcp 655 pump from swiftech) - not fancy looking but does its job.
res > pump > cpu > rad > res
and my pump is always placed below res.
 
So, another update, i've installed the new(well not new) XSPC reservoir and D5 pump, and it's all working fine again. Left the loop running to get rid of any bubbles and it's almost clear. I haven't mixed the coolant, but i do have distilled water and biocide, so i'll see how it goes.

I have a drain port!!!! yay!!!

Noticed that the XSPC D5 pump is much easier to disassemble than the Aphacool VPP755, as there is no locking nut to hold it all in place. Not that any of that matters, but i can't clean the Alphacool pump seeing as it appears to be clogged. I think I'm going to send it back.

RPM's are higher than the VPP755, but flow rate is definitely lower, not that the flow rate is an issue, it's quiet enough on full, and there is more than enough flow for my needs.

I'll see how it goes for a week or two. If i have issues again, i'll switch to distilled water and biocide.
 
So, i reckon the problem must be the Mayhem liquid. i'll never use them again, i only picked them as i was short on time in the first place, i guess you live and learn.

Even the Clear Mayhem X1 seems to be blocking the D5 pump, it took a while to kick in today, so i can see it's going stop working in a few days probably.

As soon as i have the chance, i'll drain the loop and switch to distilled water and biocide(i have both ready).
 
I would do it sooner rather than later so you dont damage your pump. If it isnt able to spin it will overheat.
 
hititnquitit said:
I would do it sooner rather than later so you dont damage your pump. If it isnt able to spin it will overheat.
Click to expand...

Done, and running well so far, have some air trapped in the monoblock, but that should clear in time.

Here's a pic, it's nothing too special, still trying to decide on what GPU to buy, spent too much on watercooling stuff, memory issues with mismatched modules(no longer), etc.

I'll fill the reservoir up in a bit
IMG_20190709_120550.jpg
 
you need to pull some of it out and shake it up..will get the air out.
 
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