Worried I have no water flow post Radiator

[SkruDe]

The below is what I posted in my build thread, but I figured this issue needed some more advice so I made a thread here about it. For Pictures of my CPU only loop, visit page 3 of this thread and scroll down (Which has been my build thread): http://www.tomshardware.com/forum/page-377755_31_100.html

"I'm a little worried, actually a lot worried that I am not getting any flow of water past the radiator outlet. I can feel the water being pushed from the Pump into the Rad when I hold the tube firmly, but from the Rad to the CPU and the CPU back to the Res it seems like there is no water in there. I can't feel it by touch when I hold it firmly, I don't feel the flow. And also the tube itself just seems to be too light and flimsy and not rigid like it would be if it was filled with water (For example my drain line and tube from pump to rad is more rigid feeling). Something doesn't seem right to me here. It's as if the water is getting blocked in the Radiator some how. Could a massive air pocket in the rad cause a complete restriction in flow? Since the radiator currently is the highest point of the system, after work today I plan to turn the whole case upside down which would then make the rad the lowest point of the system and hopefully if there is air in there it would all burb out.

I could be wrong, maybe the flow of water past the radiator can't be felt. But just the way the tube feels flimsy and not rigid raised a red flag to me last night. I'll try to turn the case upside and see what happens.

If not, then I don't know what I can do outside of buying a flow meter and installing it inbetween the block and res (end of the loop) to see if I am getting sufficient flow. I guess if anything that would give me some piece of mind but damnit it would be so frustrating to have to unstall the whole thing again and have to reinstall it"


I copy/pasted the above from my original post into here for additional help.

It's also worth noting I have done numerous flushes of the system, so I could have built up a lot of air in the rad? Also, before installing the rad I did flush it with hot water until everything was clear. I don't think there could possibly be a solid obsruction, my only idea is it could be massive air pocket? Is that possible? Has it happened before? Is it common?

Any help would be appreciated.

Thank you,


EDIT: BTW, first time water cooler here.

 

[4Ryan6]

You have to be absolutely positive there is no obstruction in the radiator, take it outside and hook it up to a water hose and run water through it, swap the tubing back and forth flushing from both directions.

Then you will know water is getting through the radiator.

 

[SkruDe]

You have to be absolutely positive there is no obstruction in the radiator, take it outside and hook it up to a water hose and run water through it, swap the tubing back and forth flushing from both directions.

Then you will know water is getting through the radiator.

This is definetely a concern. The reason I didn't think it could be an obstruction was because when I was first flushing the rad with hot water before it was installed I do recall water pooring out both ends. But I know it won't hurt to check again. If I do pull everything apart again, I will install a flow meter to make sure and give me peace of mind.

If nothing comes of the upside down idea, I will tear it all down and double check for obstructions and radiator only flow.

 

[4Ryan6]

I looked at your build thread and I'm curious regarding the clearance issue as to why you just mounted the fans on top of the case?

Why not mount the entire radiator fans and all on top of the case?

Then the clearance issue would have been history.

Looks wise you already have the fans up there?

You only have one 240 radiator so are you intending overclocking the CPU?

 

[4Ryan6]

I will install a flow meter to make sure and give me peace of mind.

Flow meters add restriction, you have to be completely sure your radiator is flowing #1, and #2, all the air is out of it, if you have to turn your computer completely upside down, (with the reservoir sealed of course!), to get it out

 

[SkruDe]

I looked at your build thread and I'm curious regarding the clearance issue as to why you just mounted the fans on top of the case?

Why not mount the entire radiator fans and all on top of the case?

Then the clearance issue would have been history.

Looks wise you already have the fans up there?

You only have one 240 radiator so are you intending overclocking the CPU?

I was only able to get one set of fans on top of the case while still allowing the case cover to be put on over top of it (which is a vented top cover for airflow). I was trying to keep everything concealed within the case itself. The top cover of the HAF-X case comes off and there is (1) 240mm fan sitting up there (and a space for optional second). I took that fan out to put the radiator fans in its place. If I placed everything up there, the cover would not close over top of them.

The kit originaly was sold as a pull config, but I wanted to mod it and make it a push pull. It was when I added the (2) fans on the bottom that I had clearance issues. So I fixed that by bringing back the whole rad/fan assembly from the MoBo, and it worked out. I was able to have two fans on bottom pushing and two fans on top pulling, while all being concealed in the case and under the top cover.

And yes, I intend to overclocking the CPU. The loop is just for the CPU.

Flow meters add restriction, you have to be completely sure your radiator is flowing #1, and #2, all the air is out of it, if you have to turn your computer completely upside down, (with the reservoir sealed of course!), to get it out

I will turn it upside once I get home. Pump on or off? Or Both?

 

[4Ryan6]

I will turn it upside once I get home. Pump on or off? Or Both?

Definitely with the pump running.

Make sure the reservoir is completely full so you don't suck air into the pump.

 

[SkruDe]

Okay, well I turned the whole system upside down and let it run for a couple minutes in that position. I noticed my drain line got half filled with air, so while it was upside down I opened my drain line and poured some water in it to top it off, then closed it back up. Since the drain line is independent to the flow of the pump, I was able to do this while pump was on.

Turned it back rightside up and I don't see any difference. The red tubing does make it really hard to see the bubbles or any water flow at all. Something I want to bring up and ask about, when I pinch the line to restrict water flow between the block and res, an area I was worried about not having flow, the pump does change it's sound like it's trying to work harder or knows its feeling the flow restriction. Is that a hint that it is working, or insignificant?

When I put my ear up to the cpu block and was able to hear some flow noise. If I turn the power off then that noise disappears. That could signify flow, but could be false since I may be hearing the sound of flow traveling upstream at the pump?

It's just so hard for me to tell if anything is flowing. The red tubing makes it very hard to see, and I don't know if the thickness of the tubing is concealing the vibration from the flow of water because I can't feel any flow by touch except from the tube directly from the pump to the rad, but I'm wondering if that vibrating I am feeling is just the pump since it is right there and moving.

 

[manofchalk]

When I was filling my loop with similar red tubing, I could see the water level inside it. Once it was full I couldn't tell either way.

Introducing restriction to the flow would make the pump work harder, which explains the increase in noise. To me that's a good sign.

One possible way to if there's flow is to drain the loop, put the case on its front and power cycle to get water back through the loop. Eventually it will hit a point where the pump/res will be full enough to have a smooth water flow, but not be completely full. You should be able to hear as the water comes from the intake port and falls to the water below.

Also if you were to put in a flow meter, it wouldn't be that arduous a process. Just drain the loop, snip the tubing where you want it, connect it up and fill it. No need to unmount anything.

 

[Motopsychojdn]

Sounds like you are experiencing the joys of a high-mounted rad, and yes,
rotating the Pc whilst running is the best way to bleed here,
but on the bright side, your Pc isn't the largest to heft around so its just a time consuming exercise,
I do the following on mine,
make sure you have a nice space on a floor with some cushioning for support/protection, and anything loose inside the case is tied/duct-taped secured to prevent it moving,
Sidepanels can usually be left off to reduce weight and allow good handholds
Remove all cables from the back of the Pc except the Psu power,
gfx cards and peripherals don't need to be plugged in for this, you do however require the power from the wall and one cable makes this easier than a nest coming from the rear of your Pc.
turn it on in the normal standing position and give it a minute to get going,
put the Pc on its side, the righthand side panel touching the floor/cushioning and rock it gently with side to side and front to back motions for a few minutes noting any air bubble movement,
try and encourage the bubbles towards your res, as res levels drop then add more water as you go, this helps force the air out
from the side position, roll it onto the roof and repeat the process then gently return to normal position,
rock it on the front and rear edges to vertical then back to normal then finally onto the window side, rinse and repeat as needed
This isn't as painful as it seems by reading and in my experience is the best way to bleed a non-standard set up, you can speed things up if you are strong enough by just lifting the Pc and rotating as described but trust me, after ten minutes your 20Kg Pc seems to weigh 80Kg,
Moto

 

[Motopsychojdn]

Okay, well I turned the whole system upside down and let it run for a couple minutes in that position. I noticed my drain line got half filled with air, so while it was upside down I opened my drain line and poured some water in it to top it off, then closed it back up. Since the drain line is independent to the flow of the pump, I was able to do this while pump was on.

Turned it back rightside up and I don't see any difference. The red tubing does make it really hard to see the bubbles or any water flow at all. Something I want to bring up and ask about, when I pinch the line to restrict water flow between the block and res, an area I was worried about not having flow, the pump does change it's sound like it's trying to work harder or knows its feeling the flow restriction. Is that a hint that it is working, or insignificant?

When I put my ear up to the cpu block and was able to hear some flow noise. If I turn the power off then that noise disappears. That could signify flow, but could be false since I may be hearing the sound of flow traveling upstream at the pump?

It's just so hard for me to tell if anything is flowing. The red tubing makes it very hard to see, and I don't know if the thickness of the tubing is concealing the vibration from the flow of water because I can't feel any flow by touch except from the tube directly from the pump to the rad, but I'm wondering if that vibrating I am feeling is just the pump since it is right there and moving.

Going by that post, add water to the line as described, reseal and run/rotate, add more water as necessary rinse and repeat until air stops getting into the line, whilst this means your loop is full, it doesn't mean theres no locks or pockets anywhere, keep rotating like I said until you have moved the Pc through every possible angle a few times, so anything trapped will be forced out, remember air like to be at the top of things so even if you can't see a pocket, you know how you can trick it into moving to where you want it to be,
the difference in noise means the pump is having to work harder to push past the restriction you cause by pinching. no worries there
you'll know you are done when you top the res to 100% and there is no drop/surge of water level when you power on, there will also be no noise from the pump/loop, apart from the gentle hum of the pump, btw you will lose small amounts to evaporation over time but its minimal and easy to monitor, and does not indicate a problem with your loop, if you are losing appreciable amounts though then check your fittings
Moto

 

[SkruDe]

This morning I continued to burp bubbles out. By turning it upside down, and tilting it from side to side, I would say I burped out about 3/4 of the length, maybe a little more, of my drain line worth of air. Then it got to the point where no way that I tilted it and positioned it could I get any more air, so I think I got most of it. Although, I still do hear from time to time the water swoosh which I am assuming means air.

So after I did the burping I put the case back right side up and opened up the res fill port. It still seemed pretty full. So then I decided to check the surge of the water when I turned the PSU off. When I turned the PSU off, I did get a little increase in water and it poured over a bit onto the top of my res. Wasn't too bad, but still I believe that means there is a little air left over in the system?

Lastly I want to say I did a little test. Since I had the radiator and (4) 120mm fans attached to it, I figured I would test to see if the water was being cooling since I have in-line water temp sensors attached to LCD's on my case that are currently hooked up and working. I figured if water temp was going down, then I should most certainly have flow! This is what I did:

I have a temp sensor in the outlet port of my reservoir (at the pump, to measure res temps) and I have another temp sensor on the outlet of radiator (to measure the cooling effectiveness). Before turning the fans on, both LCD's read 24.3 degrees Celsius. After plugging in the fans, and running at 1650 RPM's for about 15ish or so minutes, my reservoir temp dropped to 22.1 degrees and my outlet radiator temp sensor dropped to 22.0 degrees. This should be evidence enough that I do have flow continually through the system, wouldn't you think?

The rad outlet temp was just a tid bit lower then the res temp, which should be how it is. Also since I have no heat source to heat the water, the entire loop should be the relative same temperature, which it was and it dropped together as time progressed.

 

[SkruDe]

Since my build is still pretty much empty outside the MoBo and watercooling set-up inside the case, I was able to just take the entire loop out of the tower and move it around while on my kitchen counter, without having to lift and move around the case. Doing this, I was able to bleed out an addition 1/5 worth of drain tube of air in addition to the air I bled out in my previous post.

I have to think this thing is pretty much all air free now, at least close to it. And with the temperature testing I did, I think I am good to go and continue with the build.


EDIT: By the way, my drain tube length is 13". So that would give you an idea about the fractions I been using about how much air I bled out the drain tube.

 

[Motopsychojdn]

I wouldn't have a temp sensor right next to the pump, its a heatsource in its own right and may upset your readings,
but in use the entuire loop will be at the same temerature throughout within 1-3'C,
nice going on the bleeding and yes, the surge and whoosh indicate there is some air somewhere
but you have a good grasp of what you are doing and its just time now, I see no reason not to progress with the build proper, just make sure you check your fittings once you refit the loop inside
Moto

 

[4Ryan6]

You have to be absolutely positive there is no obstruction in the radiator, take it outside and hook it up to a water hose and run water through it, swap the tubing back and forth flushing from both directions.

Then you will know water is getting through the radiator.

Since my build is still pretty much empty outside the MoBo and watercooling set-up inside the case, I was able to just take the entire loop out of the tower and move it around while on my kitchen counter, without having to lift and move around the case. Doing this, I was able to bleed out an addition 1/5 worth of drain tube of air in addition to the air I bled out in my previous post.

I have to think this thing is pretty much all air free now, at least close to it. And with the temperature testing I did, I think I am good to go and continue with the build.


EDIT: By the way, my drain tube length is 13". So that would give you an idea about the fractions I been using about how much air I bled out the drain tube.

Did you ever test the radiator under water pressure like I originally suggested, to make sure it is flowing properly?

Cleaning with the boiling water does not force an obstruction out of the radiator the hot water will just go around the obstruction, pressure will force an obstruction out of the radiator.

I have pressure flushed every radiator I have and I run 60psi home water pressure and never hurt any of the radiators I have flushed, I strongly urge you to do it if you haven't, because then you will know your radiator flows properly.

That's the last you'll hear from me regarding that! Ryan

 

[SkruDe]

Best answer selected by SkruDe.

 

[Motopsychojdn]

You got sorted ok man?
Glad to help and thank you for B.a.
Moto