Litres per hour ?

ed79

ed79

ed79

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Does anyone know how many litres per hour do PC watercooling pumps shift? I'm thinking of using an aquarium pump but not sure of how much water needs to get circulated in a system.
 
My plan (that I came up with yesterday morning) is to have the radiator(s) and pump in the loft and I'm looking at these sort of pumps http://www.theaquariumshop.co.uk/index.php?cPath=469_23 but I wasn't sure how powerful they would need to be to lift the additional water up 1 floor into the loft (from my bedroom). I'm guessing normal PC pumps don't move that much water, but obviously my idea would involve having more water in the system.
 
They are mainly quoted in l/hr now.

DDC is 600l/hr on the latest model, D5 Vario is 1200 on the highest speed setting.

Just looking at the pump specification pages would have given you these figures.

Aquarium pumps are actually very good, primarily because valuable, often beloved, animals die if they stop working, so they tend to be very accurate in terms of their rated power and very reliable. They also tend to be mains powered unfortunately.
 
ed79 said:
My plan (that I came up with yesterday morning) is to have the radiator(s) and pump in the loft and I'm looking at these sort of pumps http://www.theaquariumshop.co.uk/index.php?cPath=469_23 but I wasn't sure how powerful they would need to be to lift the additional water up 1 floor into the loft (from my bedroom). I'm guessing normal PC pumps don't move that much water, but obviously my idea would involve having more water in the system.
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I don't know why you think PC pumps wouldn't be every bit as oomphy as Aquarium pumps (they are) or that an aquarium pump would lift water 3m. They can't reliably. You'll need a central heating pump for that. And that won't be £100, it'll be £300.
 
Yea, to pump the water all the way up to your loft your gonna need a pretty damn powerful pump!! What was your thinking here? Could you not just put your rads in the same room but away from the PC a bit? Thats not too uncommonly done and a lot easier!!
 
It isn't just about flow rate, its about head pressure at a given flow rate. 3m of head pressure will be difficult to find in a small pump. If you're certain this is the way you want to go, you either need a central heating pump, or possible pump water from computer to a reservoir 1.5M above it, then use a second loop pumping water from this reservoir through the radiators in the loft

it would be a hell of a lot easier to put the computer in the loft and run a long monitor extension cable down from it
 
http://martin.skinneelabs.com/MartinsFlowRateEstimator.html

Is a useful flow rate estimator (link to download a zip file for it is on that page) where you can input what pump, waterblocks, length and diameter of tubing, 90 degree bends etc and it gives a reasonably accurate flowrate. You choose from drop-down menus of pumps, blocks etc for which the pressure-flow rate (for pumps) and pressure drop (for blocks, tubing etc) is known, and it tells you the flowrate to expect. For modern waterblocks you want a flow-rate of about 1gallon per minute (~4.5l/min) or above. Over 1gpm there is diminishing return of cooling performance - 1gpm gives about 90% of the maximum you can really hope to achieve iirc (as with increasing flowrates for modern, high surface area blocks the transfer of heat from copper to water becomes the limiting factor, and with increasing flowrate you need a more powerful pump that dumps more heat into the water loop). :)
 
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er as long as the circuit is a loop back down again, it doesnt need a head pressure of 3m as its just a circulation pump.

Head pressure refers to how high it will lift the water without the aid of mavity pulling down on the other side. ie for a fountain.

As long as the system is sealed so that mavity is acting on the same amount of water on the downside, a pond pump should manage to circulate the water.

Issues I would have is that the whole system will end up being below ambient in winter, and the loft is likely to be well above ambient during summer, so you may find it ineffective at cooling in summer, and have condensation issues in winter.
 
Ah, I did wonder why I didn't hear of more people doing this sort of thing.

My thinking was that my case can really only fit a single 120mm radiator in, and I want to cool an i7 and northbridge. I didn't like the option of an external 120.3 radiator so thought, why not install it all in the loft where it can be silent and out of sight.

If that's not realistic then it's OK as I haven't spent any money yet!
 
And thanks everyone for your replies.

I haven't looked much into the PC component choice side yet. I wanted to check the water circulation idea would work first.

The idea in my head was the CPU and northbridge on 1 120.3 rad and in the future a 2 card SLI setup on another 120.3.
 
Dr Who said:
er as long as the circuit is a loop back down again, it doesnt need a head pressure of 3m as its just a circulation pump.

Head pressure refers to how high it will lift the water without the aid of mavity pulling down on the other side. ie for a fountain.

As long as the system is sealed so that mavity is acting on the same amount of water on the downside, a pond pump should manage to circulate the water.
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Good in theory. Doesn't actually work in reality. Probably because it's very hard to get a true sealed system.
 
Works fine on Koi Pond Filter systems, isnt that hard to seal a system, but you wont get away with just barbs as the weight of water in the system will create a massive pressure at the bottom of the rig!
 
Dr Who said:
Works fine on Koi Pond Filter systems, isnt that hard to seal a system, but you wont get away with just barbs as the weight of water in the system will create a massive pressure at the bottom of the rig!
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The water level in my T-line always drops when the pump starts, even when I've just filled it right to the top. Plus, water finds its way through the tubing after a while anyhow, so it stops being a truly sealed system after a bit.
 
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