Air in GPU waterblock

[toilet pepper]

Hi! I just finished my first custom loop over the weekend and just noticed something odd. There GPU waterblock has an air gap in it and I cant seem to get it out. I tried rotating the case and that worked for a while but eventually the air gap goes back to the same spot of the GPU.

Should I be worried? I think the "top" most part of the block is where the VRMs are and the coolant is not touching it. It is also not the highest part of the loop.

 

[skizzo]

if you're trying to get rid of large air gap/bubble like that then I recommend running the pump max speed and it will, eventually, evacuate in my experience. moving the case around is a good practice too which you've done already and can keep doing as needed. what you're trying to do there is create a different high point the bubble will want to naturally travel too. ever play one of those kid games with marbles in them and its a maze, you rotate them around to get the marble to the end? thats kinda what you're trying to do when you move the case around to get the bubble out lol. sometimes its more of a light shake that is needed too. that bubble area looks to be a large enough spot that you wouldn't want it like this forever. nothing to fret or worry over to be clear though, nothing is in immediate harm. but I would run the pump max until it works itself out. could be a few hours, could require time over a couple days. I have a vertical rad in my system and it regularly gets a little air trapped in the top of it. noticeable because when my system randomly ramps up from a high load you hear the "glug glug" bubble sounds and then see a handful of bubbles pop out of the rad's exit and only that point. and then I watch my res lower just slightly as a result, because the air ends up in the top of my res rather than top of the vertical rad. it being the highest part of the loop is working against you but it should be possible to get rid it of with pump maxed out and patience

 

[ThrashZone]

Hi,
Nice keyboard but it's blocking the rest of the loop
Sure way to get a d5 pump to run full blast is disconnect the pwm wire from the board
If this is a vario d5 with dial set it on 5 for a while.

Might show us the rest of the loop and which way the water flows through it or simply check for loop clashes.

 

[thesmokingman]

You don't have enough pump. During bleeding you should have had the pump at max as thrash describes above. Tilt the thing so the bubbles get sucked in and add more fluid. Just watched the Friend Reunion, and as Ross says, PIVOT! PIVOT PIVOT! lol. That box is tiny so set pump to max and pivot it around until the bubbles get sucked up. Add more fluid, rinse repeat until there's no bubbles, then close it down.

 

[sneekypeet]

You got swivel fittings on the card. I'd pull the 24-pin and the card. Jump the 24-pin so the pump powers up, then move the card about till the air comes out. Plug card back in, plug 24-pin back on motherboard, bobs your uncle, it's fixed.

 

[toilet pepper]

I just tilted it while runnning the pump at max speed. It made a loud gushing sound for a few minutes and normalized now. However. The water level became worse.

 

[ThrashZone]

Hi,
Yep water temp is 40c that's bad.

 

[thesmokingman]

This is why beginners should not try builds like this.

 

[ThrashZone]

Hi,
Bad pump can happen to anyone.
Haven't said much about it but is this a dcc pump or d5 ?

 

[toilet pepper]

Hi,
Yep water temp is 40c that's bad.

Hi. That is at 300W load right now when I took the pic. My Ambient is around 27C. BTW the loop order is Pump>GPU>Rad>CPU>Pump. That's a DDC. There's no way a D5 can fit in there.

 

[cvaldes]

That's the right temperature window for the cooling loop exhaust from an RTX 3080's waterblock.

In my system, the GPU's exhaust coolant temperature is 44 °C right before entering the radiator when the GPU is maxxed out (e.g., Unigine Heaven benchmark), 354W load (with the ASUS GPU TweakII standard overclock).

My loop order is Pump > Reservoir > CPU > 360mm rad (thin) > GPU > inline thermal sensor > 360mm rad (30mm thick) > Pump

Where the idle temperature settles back to depends a lot on the ambient temperature. In the summer months, the loop idle is about 31 °C.

 

[ThrashZone]

Hi. That is at 300W load right now when I took the pic. My Ambient is around 27C. BTW the loop order is Pump>GPU>Rad>CPU>Pump. That's a DDC. There's no way a D5 can fit in there.

Hi,
Problem is that pump is not working properly most use them because they have more head pressure than d5's but this one has none.
DCC pumps are air cooled just for the record.

Hi,
Where is the reservoir ?

 

[Deleted member 24505]

Imo DDC's are rubbish, I will only use a D5 now. I guess if you can only fit a DDC in you will have to. If rotating it while running does not clear the bubbles, the pump is not good enough.

 

[ThrashZone]

Imo DDC's are rubbish, I will only use a D5 now. I guess if you can only fit a DDC in you will have to. If rotating it while running does not clear the bubbles, the pump is not good enough.

Hi,
Issue is the air does get out of the gpu block
Bad thing is I've not seen a reservoir where the air can escape and fluid replaces it in other places in the loop.

 

[Deleted member 24505]

Hi,
Issue is the air does get out of the gpu block
Bad thing is I've not seen a reservoir where the air can escape and fluid replaces it in other places in the loop.

Maybe a barb with a tube on it from the res into a bigger container of fluid? maybe the air will bleed into the container

 

[cvaldes]

Where is the reservoir ?

It's a pump-reservoir combo, the device to the right of the power supply. Pretty much a necessity for an SFF build like this.

One tactic that has worked for me in the past was to introduce more liquid into the loop at a different location (with the goal of reducing loop bubbles), typically through my drain hose. I can't tell from the photos whether or not this is achievable in this build.

 

[Deleted member 24505]

It's a pump-reservoir combo.

It has a pretty small volume too, which does not help

 

[ThrashZone]

Hi,
Indeed air locked in it.

 

[cvaldes]

It has a pretty small volume too, which does not help

For sure not easy, but not impossible either.

I tested a loop with similar components including a pump-res combo from Alphacool (Eisstation I think) with a similar volume. Someday I will probably use this setup on my NZXT H1. It's odd looking because most of the cooling loop is outside the case (piggybacked on the rear grate) including pump-reservoir combo, 2x 120mm fans, and 240mm radiator.

 

[thesmokingman]

This is where I would stick a long piece of tube on the res giving it a larger water source until it was fully bled, then ya remove the hose.

 

[toilet pepper]

Maybe a barb with a tube on it from the res into a bigger container of fluid? maybe the air will bleed into the container

I'll most likely try this later. That's how I filled it and it might be the reason this is happening. Will send an update soon.

Here's what a GPUZ screenie looks like right now. I'd say the temps are decent for an ambien of 27-28C. I'm just worried that the coolant is not touching the top-most part of the block and that is where the VRM are. Theoretically, I would assume that the coolant does not need to touch that part of the block itself as the rest of the block is getting adequate coolant flow. But I still value other people's opinions if this needs to be fixed.

 

[thesmokingman]

That amount of air is not ok.

 

[cvaldes]

I just noticed from your other related thread

Need advice on SFF Custom Loop

I now have almost all the parts for my Meshlicious custom loop and desperately need help before I build it. With the Meshlicious you can place a singles rad at the front. The first question is the fan placement and orientation. Should the rad be the one that is attached to the case instead of...

www.techpowerup.com

that your radiator is not correctly oriented. The couplings should be at the bottom of a vertically mounted radiator.

This GamersNexus video -- while focusing on AIO coolers -- is valid for custom loops:

This is likely contributing to your air gap problems.

 

[toilet pepper]

I just noticed from your other related thread

Need advice on SFF Custom Loop

I now have almost all the parts for my Meshlicious custom loop and desperately need help before I build it. With the Meshlicious you can place a singles rad at the front. The first question is the fan placement and orientation. Should the rad be the one that is attached to the case instead of...

www.techpowerup.com

that your radiator is not correctly oriented. The couplings should be at the bottom of a vertically mounted radiator.

This GamersNexus video -- while focusing on AIO coolers -- is valid for custom loops:

This is likely contributing to your air gap problems.

Yep. Saw that GN video a lot of times. They suggest that because air gets trapped in the pump which can kill it.

My orientation makes sure that doesnt happen as it is at the very bottom of the loop.

Thank you for the input though. I'll try all the suggestions here before I decide to redo the loop.

 

[Valantar]

Hi,
Yep water temp is 40c that's bad.

Why is it bad? I've been running loops in that temperature range for years with zero problems. Cleaned out my blocks last fall after running them since 2017 (changed liquid twice, no other maintenance) and they were nearly spotless. For an SFF loop with powerful components that's perfectly fine. Heck, my current loop (Meshlicious, single 280mm rad with a 6900XT and 5800X) hits about 45°C under full load (ambients are hot now in summer, 27-29°C).

Op: your pump isn't powerful enough to force that air out, and despite that pocket not being the highest point in your loop it is the highest where air is easily trapped, given that your radiator has its ports up top. You've also built a loop that looks difficult to bleed. With the reservoir all the way at the bottom and tubing going into its top (i.e. no dead space at the top of the res in which air can gather) any air in the system will eventually gather in the gpu block. You need to bleed your loop more thoroughly - get all air out of there. All of it. Where is your fill port? Attach a length of spare tubing to it, fill it with liquid, plug the end. Flip the system so that this "reservoir" is the highest point. Run the pump on and off and let air gather in the spare tubing. Refill with water if necessary. When the loop is bled, remove the tubing and plug the fill port.