Varying fill level in res

SnowmanFromHell

New member
Howdy folks,

just a quick question for the watercooling veterans:
is it normal for the water level in the res to drop when you turn on the pump? so, say you fill the system, bleed it etc. should the water level then change when you turn on the pump (level drops... but goes back up when you turn off the pump) or should it remain the same at all times?
 
i have a 2 bay res and it prety much stays the same level all the time.

technically the only way the water level can rise in your res is if the water in your system gets replaced by something els...

are you sure your res is sealed (has the little stopper in it?)
it shouldnt be able to change level unless air enters the res to replace the water thats moved..
 
i have a 2 bay res and it prety much stays the same level all the time.

technically the only way the water level can rise in your res is if the water in your system gets replaced by something els...

are you sure your res is sealed (has the little stopper in it?)
it shouldnt be able to change level unless air enters the res to replace the water thats moved..

yes, res is sealed (tried it with open res as well, same result)... where does the water go? :huh:
 
the water is just being used in the system. i wouldnt wory about where it goes.
id worry about how its able to come back in a sealed system more than anything.

i would personally think the res isnt fully sealed. (water can then come in to the res pushing air out and replacing it. then when turned on the water can go off and air can enter the res replacing it..

but air is compressible so if its only a little difference i would probably not worry about it.
but if the res goes from almost empty to pretty much full then id be checking for air leaks in the res..

also does your res return water under the water line?

Any way basic Principal is. if you fill a straw up with water then put your thumb over one end. the water wont come out of the open end because air cant replace it..
 
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but if the res goes from almost empty to pretty much full then id be checking for air leaks in the res..

no no, it's basically like 3-5mm, so not really much

also does your res return water under the water line?

yes... the pump doesn't draw any air, and both inlet and outlet of the res are at the bottom (and the res is probably 80% full), so there's more than enough water to draw
 
This is normal behavior. As the pump starts it creates an area or high pressure in front and low pressure behind which causes water to be sucked in if your res goes directly into the pump. If the level drops a few mm while the pump is running and returns to normal when it shuts down, it is normal. If the water level drops and never returns you need to look for a leak.
 
I think the tubing flexes and stretches a bit when it gets warm and from the pressure inside when in use. I think this only happens when the tubing is still new though.

I find the level in the res will drop a bit for the first few months and then no more.
 
you sir have an air pocket somewhere in your loop. And when you turn on the pump it compresses and lowers your level, and when you turn it off it releases that pressure. Its time to do the computer rock/tilt/shake and see if you can dislodge it.
 
you sir have an air pocket somewhere in your loop. And when you turn on the pump it compresses and lowers your level, and when you turn it off it releases that pressure. Its time to do the computer rock/tilt/shake and see if you can dislodge it.

Aaaahhh..... essentially hasn't been bled properly?
 
that what it sounds like to me bro. once the viods are all full of water you should not see it rise and fall in the rez at all. Unless your seeing turbulence which would actually be seen as a rise in levels when on.
 
that what it sounds like to me bro. once the viods are all full of water you should not see it rise and fall in the rez at all. Unless your seeing turbulence which would actually be seen as a rise in levels when on.

the amount of drop/rize described makes me think it is just the air in the res being extended due to pressure diferential caused by the pump.
thats why i said i wouldnt worry about it.
I guess there could be a void in a rad some where but i think its most likely just because of the 20% void in the res.
if it had been a larger variance of level i would have been more inclined to worry about it.
 
you sir have an air pocket somewhere in your loop. And when you turn on the pump it compresses and lowers your level, and when you turn it off it releases that pressure. Its time to do the computer rock/tilt/shake and see if you can dislodge it.

well... shit :D ... not what I was hoping to hear, but I'll give it a try... what a drag... that thing was a bitch to get it bled to the current state, if there's some remaining air in the loop it's gonna take forever and a day to get out :mellow:
 
I now run a more compact loop with a tube rez versus my old loop which was massive and used a bay rez. In neither did I ever see the water lvl rise or lower with pump on or off, after it was complete void of air. Now while filling yeah it rose and fell.
 
yeah, rocked it back and forth a bit more extremely than before and in a certain position there's some gurgling noise... oh joy, endless hours of fun bleeding the remaining air out :)
anyway, thanks for your help and getting me on the right way
 
dont be afraid to give it a good rocking I sometimes had to tilt it on a corner of the case whilst doing the rock and shake lol. That vigorous movement can force the air to dislodge.
 
dont be afraid to give it a good rocking I sometimes had to tilt it on a corner of the case whilst doing the rock and shake lol. That vigorous movement can force the air to dislodge.

hehe already did that... guess I'll have to basically lay it on one side (trying to make sure the pump still draws water), or maybe turn it off and turn it upside down or something... the problem is I have a rad in the top, so if the air is at the highest point the pump would have to suck the air down to get it out... not sure it'll work... maybe I'll try to set the pump to max or something, we'll see...
 
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