D5 Pump Not Strong Enough?

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Hi everyone, I just got a Singularity Computers Protium D5 reservoir and an alphacool VP655 D5 PWM pump. I?m testing them out of my system to make sure that the pump works fine before installing it in my build. Water travels from the radiator up to the inlet of the pump/reservoir and then it leaves the pump into the green tube (testing only) going back into the radiator. My question is this, there is a huge air bubble in the green tube close to the outlet of the pump and it looks like the pump isn?t able to pump the water strong enough causing the massive air bubble. It looks like water is just trickling down the green tube. Is this normal? I made a video and posted it in the link below.

At first, I thought this might be caused by the 90 degree inlet bend restricting the water flow into the pump. But then again, the pump is gravity fed by the reservoir so there is plenty of water feeding the pump and this shouldn?t be a feeding/intake problem.

I tried using a different D5 pump (Laing D5T Vario) and I get the same result. I also tried a different PSU (EVGA 850W) and get the same result.

So is that massive air bubble normal when water is leaving the pump? Or do I have to wait for it to naturally bleed itself out of the loop? I?m worried that my pump isn?t strong enough, but then again, I know D5 pumps can push through a lot.

Any comments/suggestions would be helpful, thanks.




https://youtu.be/HQ9Lx82aqIw
 
Like D4N said, you should tip it to remove the air pockets.
Try to increase and decrease the pump speed, sometimes doing this a few times helps removing air pockets.
 
If it’s variable speed, turn it up a bit to see if it changes. Usually I have found once the air is out, they are okay. You could try it without the cap on the reservoir as well just to see if it helps bleed it.
 
Sounds like the pump has lots of air in it. Top up the reservoir more or run it without screwing in the top plug on the reservoir in case it's a build up of pressure causing lots of air to be stuck in the pump.
 
ok, thanks guys, ill give that a try- remove cap from the top and fill it up with more water. Also, I can see a lot of air bubbles circulating and both of my pumps are a bit loud, sounds like a crackling noise. Is this sound caused by air bubbles in the pump?

Besides tilting and rotating to get the air out, anything i can do to remove all the air?
 
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One thing that just came to my mind. My radiator is higher than my reservoir, so im guessing as i fill in my reservoir, the radiator will be filled up to the same level as well. However, once i fill my reservoir to the max, there is still a gap at the top of my radiator. Will this top section be filled with water too as the pump pushes the water in? or will the water level of the radiator always match the reservoir? The reason why im asking is because i want the radiator to be completely full even though my reservoir is lower.
 
It's a pwm pump. When i got mine everybody told me i would need some pwm power otherwise it would pump as low speed as possible. I'm not sure if it's possible to do this without using and powering the motherboard...
 
One thing that just came to my mind. My radiator is higher than my reservoir, so im guessing as i fill in my reservoir, the radiator will be filled up to the same level as well. However, once i fill my reservoir to the max, there is still a gap at the top of my radiator. Will this top section be filled with water too as the pump pushes the water in? or will the water level of the radiator always match the reservoir? The reason why im asking is because i want the radiator to be completely full even though my reservoir is lower.
Keep filling the reservoir while it's powered until the level stops dropping.
 
Keep filling the reservoir while it's powered until the level stops dropping.

Well yes, obviously I did that. I was just wondering if it is possible for the radiator (sitting higher) to be completely full while my reservoir (sitting lower) to not be completely full with the water level stabilizing.
 
Well yes, obviously I did that. I was just wondering if it is possible for the radiator (sitting higher) to be completely full while my reservoir (sitting lower) to not be completely full with the water level stabilizing.
Well obviously if it's got a pump connected it could have half the water in aslong as there is enough to be pumped around...
 
It's a pwm pump. When i got mine everybody told me i would need some pwm power otherwise it would pump as low speed as possible. I'm not sure if it's possible to do this without using and powering the motherboard...

Noctua do a PWM fan controller that is sata powered. That might work to alter the speed without a motherboard.
 
Is the reservoir sealed? If so, remove one of the seal plugs. when filling a loop it's important that the loop is not completely sealed.
 
Have you plugged in the pump PWM header into the motherboard?

I found when I did a rebuild and added some components that I was struggling with air bubbles when filling and was getting lots of grief. Turned out that my motherboard even though it didn't have the main power connector was still controlling the pump and a result running the pump at a third speed. Unhooking it from the MB caused it to go to full RPM and the bubbles were pushed around straight away.
 
Alright, I think I fixed it after some testing today.

Here is a video of the pump spinning, notice how its spinning quite fast and generating a lot of air bubbles? The air bubbles are then fed back out from the pump into the water loop. Also, notice how loud the pump is? With all the pumps I used in the past, it never sounded this loud.

https://youtu.be/ojIQlHWkOr4

After connecting it to a separate computer, this is how my pump sound like now. It’s completely inaudible (the background noise you hear is from the computer at the back). There are minimal air bubbles in the reservoir and inlet and outlet tubes from the pump. This is how quiet I am used to with my previous pumps. When I went into the BIOS, my pump was spinning at 1800RPM (Normal Speed). If I increased the pump speed to 4787RPM (Full Speed), I can replicate the loudness in the first video which sounds like a turbine. I also tried used a different inlet (top of my multi-port cap) on my reservoir and the water seems to be flowing well and not trickling or splashing back in.

https://youtu.be/lYzx9GVfms0

So all in all, it was indeed the pump speed/RPM. After modulating its speed, there are less air bubbles, less turbulence and the pump is much quiet now. I still did do a lot of tilting and rotating to bleed out the air bubbles as much as possible, but this looks and sounds much better than before. I’m more confident with my pump now and will reinstall it back in my system.
 
Hi everyone, here is an update on my build. Pump and reservoir has been installed back into my rig and I’m just leak testing everything. So far, there are no leaks, however, I’m wondering if my pump flow is being restricted. As you can see from the picture below, I have a sharp 90 degree angle as the pump outlet, and sharp 90 degree angle as the pump inlet. I’ve seen other builds with these angled fittings, so I thought it would be okay. Would the 90 degrees outlet restrict the water coming out of the pump? The reason why im asking is because I have a flow meter right after the water leaves the pump and it is showing 10 revs/second and 0.4L/min which is really low, especially when the pump is on full speed at 4700 RPM. My flow meter works perfectly as I tested it out before on my other rigs. On my other rigs, when my D5 Vario was on setting 3-4, it would show 40 rev/sec and 1.8L/min. But now on my D5 PWM pump it is showing much less flow at max speed. I also included a video of this at the bottom too, along with my entire water loop. I have a CPU and GPU waterblock and two 360 rad.





Here is the video:
https://youtu.be/otqEArfF0vI
 
I think the problem is the loop isn't completely filled yet.

Tilt the case to get the air out of the rads/waterblocks but be careful that the reservoir doesn't empty as there could still be a lot of air in the loop.
 
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