Dual eheim 1250?

[NeoReaper]

does it make sense to have more than one eheim 1250 waterpump in a watercooling setup. i considered upgrading my pump but then i started wondering if it would make more sense to purchase a 2nd one instead.

[jman1310]

what are you pumping through?

i'm running 1 1250>MCW30>MCW60>Apogee>BX2>BX2>res
i'm very happy with my temps

it doesn't take a lot of flow to keep things cool and you quickly add more heat from adding pumps than temp drop from higher flow

so i would suggest saving your money - 1 1250 is fine
buy better rads or blocks if the money has to be spent

[NeoReaper]

i have a dangerden tdx waterblock and a oldschool heatercore from d-tek customs. 1/2" tubing in system

[Ice Czar]

http://www.pumped101.com/#series_parallel
http://www.pumpworld.com/parallel_pumping_identical.htm
http://www.engineersedge.com/fluid_f...mps_series.htm

parallel to increse flow
series to increase pressure
then there is always failover

of course this assumes the rest of the loop can deal with and benefit from a 2nd pump

pump-heat (kinetic energy) is real, and you quickly see diminishing returns

[Long Haired Git]

Approximator BETA

OOops, eheim 1250 is broken, will need to fix that! :-D

[skaktuss]

i wouldnt use 2x1250, becouse of the heatdump. eheim 1250 is very hot pump!

[billbartuska]

Originally Posted by NeoReaper

does it make sense to have more than one eheim 1250 waterpump in a watercooling setup. i considered upgrading my pump but then i started wondering if it would make more sense to purchase a 2nd one instead.

ben805 on xtrenesystens.org, 04-04-2006:
http://www.xtremesystems.org/forums/...ad.php?t=95014

Quote

Straight from Cathar at http://forums.procooling.com/vbb/sho...t=10825&page=8

Did a heat-dump test on the RD-30. It's heat dump into the loop is actually fairly high, despite being a magnetic armature design. This is supported in that the casing barely gets warm.

Basically measured that around 83% of the pump's power draw gets passed into the water during in-line use.

Pump was measured to draw 28.1W. Calculated heat dump was 23.2W, with around an estimated 10% margin of error on that value.

Plugging that back in to the maths of the first two posts, this works out to:

+20.7C => Iwaki RD-30 @ 18.0v
+20.8C => 2 x Swiftech MCP600 @ 13.8v (series)
+20.9C => Swiftech MCP600 @ 13.8v
+21.1C => Iwaki MD-20RZ @ 60Hz
+21.1C => 2 x Swiftech MCP600 @ 12.0v (series)
+21.2C => Iwaki MD-20RZ @ 50Hz
+21.4C => Swiftech MCP600 @ 12.0v
+21.4C => 2 x Eheim 1048 (series)
+21.5C => Iwaki MD-15R @ 60Hz
+21.6C => Swiftech MCP650 @ 12.0v
+21.6C => Iwaki MD-30RZ @ 50Hz
+21.7C => Iwaki MD-30RZ @ 60Hz
+21.9C => Eheim 1250 <=================
+22.3C => Eheim 1048
+23.3C => Eheim 1046

End quote

[redleader]

Thats bizzare. I metered my 1250 at 9w years ago on a Maze2 block. Does flow restriction really make that big a difference?

[billbartuska]

Originally Posted by redleader

Thats bizzare. I metered my 1250 at 9w years ago on a Maze2 block. Does flow restriction really make that big a difference?

Not the same pump, but:
MCP-655
Peak Pressure Head and Power Draw (Watts at dead-head) - measured by Cathar
#5, 4.10mH2O, 21.0W
#4, 3.05mH2O, 14.5W
#3, 2.25mH2O, 11.0W
#2, 1.40mH2O, 7.0W
#1, 0.60mH2O, 4.0W

As I would assume, higher pressure = higher power usage = higher heat dump. The data is rather dramatic.

[ReD.SkY]

The only resaon that there is higher power usage when more pressure is needed is because the motor has to turn faster.

as for the dual 1250's... its would add mroe head, but the head thats added will be cancelled out by the heat thats added.

A 50Z however dumps 8 watts of heat into the loop. so 2 x 50Z in series = 0.3c lower temps. All of cathar's test werent with a Storm or MP-05 and a GPU or 2 and a triple rad.

in the scenario with a high restriction block, SLI, and a triple rad, the 2 x 50Z would have a greater performance gain versus the one 50Z possibly 1c or more