dual pumps in a distilled loop

[Manoa]

I have a LOWARA running alone with around 240 LPH but in the past I ran a MCP355 with much higher flow that helped with temperatures but now I see in this new loop the flow is much lower than before, it probably becuase I have more components and a slower pump, so what I wanne do is add another pump and the problem is I don't know if it is a good idea to mix diffrent pumps, will the strong be "pushing" the weak ? or it dosen't realy mater since both will be helping ? should they be connected in parallel or in serial ?

 

[basco]

wouldn't you be better of with running 1x moar power pump instead of 2 different ?
the power pump renders the slower useless in my small opinion.
but i am eager to hear from others.

 

[ThrashZone]

Hi,
Best to use identical pumps
Slower pump could act like an anchor and kill flow or just as a pass through doing nothing for what it was intended to do

Post a image or two of the loop
I use dual ek D5 pwm pumps in a corsair 450d case lol and yes it's snug
But with identical D5 pumps even though one is a pump reservoir combo and the other is a D5 top they do well

 

[Manoa]

would it also kill the flow if the pumps were connected in parallel ?

http://manoa.dream.org.il/Pics/loop/P1000719.JPG

http://manoa.dream.org.il/Pics/loop/P1000720.JPG

http://manoa.dream.org.il/Pics/loop/P1000721.JPG

http://manoa.dream.org.il/Pics/loop/P1000722.JPG

http://manoa.dream.org.il/Pics/loop/P1000723.JPG

http://manoa.dream.org.il/Pics/loop/P1000724.JPG

pictures only show the first system, it cooling another 4 computers

 

[EarthDog]

You only need ~1.5GPM flow. Anything past that is diminishing returns, really.

 

[Manoa]

one of the problem is when I set the pump from 12V to 24V thare is no change in water speed :x it stay same 240 LPH, I try also set pump to speed 4/5 with voltage 15,18,21 nothing help :x it don't increase power, 1.5 GPM it 345 LPH so I need another 100 LPH but if I can't do this with voltage to the pump (this is whay I buyed it)... I don't wanne buy more pumps realy :x thare is no need for that becuase I have except the MCP355 also a MCP 35X and they are very similar performance so if you say with big pump diffrences it can slow each other down, what if diffrence is small ? mybe then it doesn't slow each other ? what about parallel pump connection ? if I split from the container to 2 pumps and then reunite with another split ?

 

[basco]

i have some pics from pcgh pimp test:
hope this helps:
1st pic means decrease in pressure on cpu heatsink with a rate of flow at 60L\h
2nd pic rate of flow sorted after loudness\ and left side is with 1x heatsink and right side 4x heatsinks
3rd pic pump pressure sorted after loudness and 1mbar is 1cm water column


i think this confirms what Earthdog said.

corsair is a labeled lowara pwm version
watercool is a lowara norm

prices range from 50.- euros to 200.- and even the cheapest can push enough throughput is their consens.

 

[Manoa]

thank that's nice, but I am not yet in 1.5, I am in 1.0 :x I wanne increase to 1.5

 

[EarthDog]

1-1.5 is the sweetepot. You're chasing a degree or so.

 

[Thrax]

1-1.5 is the sweetepot. You're chasing a degree or so.

thank that's nice, but I am not yet in 1.5, I am in 1.0 :x I wanne increase to 1.5

Fully agree, flow rate isn't too important in my opinion. Cooling capacity of the loop i.e radiators and fans have a bigger impact.