D5 Pump Not Strong Enough?

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://i.postimg.cc/wx5d9HYB/20210614-160712.jpg

https://youtu.be/HQ9Lx82aqIw

I am not sure why the vario would not work, but most of the D5 PWM will default to a low speed without a PWM signal.

Quote:

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Originally Posted by turok_t

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://i.postimg.cc/wx5d9HYB/20210614-160712.jpg

https://youtu.be/HQ9Lx82aqIw

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Did you figure this out? The pressure is good coming into the pump?

yup i figured it out, thanks!

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.

https://i.postimg.cc/xTkpqPfs/20210715-1837188.jpg
https://i.postimg.cc/nrmdSHwy/20210715-183717.jpg
https://i.postimg.cc/VLyZrCJm/20210715-185104.jpg

Here is the video:
https://youtu.be/otqEArfF0vI