AC Pump - Eheim 1250 or not?

[Gemütlichkeit]

My next build will have Tygon 1/2"ID 3/4"OD tubing, 3 Black Ice GT Stealth 280 Radiators (yes, I know 2 would probably be overkill--don't care--still getting 3), an AC pump (vice 12V), to cool a Heatkiller Rev 3.0 754/939/AM2 CPU block and a Powercolor LCS AX5870 graphics card.

Radiators & pump will be in a separate enclosure and connected to case via a run of tubing & quick disconnects.

Currently I'm looking at getting an Eheim 1250 Pump. Considerations are: AC powered, dependability, noise level, and overkill. The overkill part pertains to pump head and flow rate.

Is the 1250 the right choice? If not, what are some alternatives and why would they be better?

Thanks in advance for your suggestions/comments. ~ Gem

 

[Appa]

Laing D5 is hard to beat! aka Swiftech MCP-655. There are so many better pumps out there, the Eheim design is quite dated and is known to have issues with it's axis.

I'm running dual loops with two MCP-655Bs and they are dead quiet, my Triebwerk fans are louder than BOTH pumps.

 

[Gemütlichkeit]

Thanks for your comment. The 655 was on my list, but it is 12v vice AC and there are conflicting accounts about its noise levels. http://www.crazypc.com/products/mcp655-b-9336B.html

I am will reconsider my 110V requirement if there is a clearly better 12v option. I admit, I liked what you had to say about the 655.

 

[Appa]

Oh I see what you mean.

The standard MCP-655 w/ speed adjustment does have a bit of an electrical whine. Not much at all, but it is there. I know this because I replaced two of them with two of the silent 655-B models. These models do not have speed adjustment and are locked in at 4300rpm, as well as having some adjustments to the control circuitry to make them silent.

When both of mine were running for the first time, I had to put my hand on them to make sure they were running! They are that quiet.

Good luck with your search!

 

[undertheradar]

The eheims are good pumps. They are AC though too so turning them on and off all the time causes more wear than just leaving them on (which is what I do). Then you can expect a very long and silent service life. OTOH, even though they offer higher flow than most, they are more flow biased than most DC pumps now offered in this industry, so while the potential to move 300+ gph is there... as soon as you go putting on highly restrictive waterblocks, a radiator, and lots of hose, the back-pressure adds up fast. In the end, you will likely only get about 100-150gph of flow from one of these pumps because they just dont handle pressure that well. I use two eheim 1250's in series (to boost pressure), for an external floor standing radiator. I use watercool blocks in series for the GPU, CPU, and NB, but the radiator itself isnt restrictive and I use 1/2" tygon hose, so the back pressure on the pumps is kept to a minimum. Overall, if I had to do it again, I would just opt for a single DC pump though. Even though they dont generate the possible 300gph+ peak flow of the eheim, the can get close, and they are pressure biased pumps... almost double the rpm's goes a long way to handle pressure.

 

[Gemütlichkeit]

Question has become moot... we open Xmas presents on Xmas eve and I now have in my possession an Eheim 1250. Your post is reassuring though. I also got the 3 Black Ice GT Stealth 280 Radiators, Tygon 1/2-3/4 tubing, and misc fittings that were on my list.

I'm planning on building a plexi enclosure which will house the rads, pump, and a Vornado fan (http://www.vornado.com/ProductDetail.aspx?ISC_Category=V102). I will be running the rads in parallel--series seems like it would result in the coolest exit temp, but my guess is it's probably not that much difference (in parallel, the divided flow spends 3x longer in the rads), and parallel will present less flow restriction.

The unknowns are how much flow restriction the Heatkiller CPU block in series with a PowerColor LCS AX5870 EK water block will slow things down. I think I read somewhere that the Heatkiller was a relatively high flow block, not sure about the EK. Will have to wait for a while to find out because of the largely theoretical existence of the PowerColor LCS AX5870 (and the Silverstone FT02 case) that I'm waiting on.

Thanks for your comment. I expect I'll document the build on a web site once I get all the parts and get started.

~ Gem

 

[Psi*]

I wired in a 12 VDC relay to switch on the WC system when the PSU switches on ... in the normal way. The relay is a SPDT which has N/C (normally closed) & N/O (normally open) connections. So the 110 VAC to the pump is connected to N/O & common goes to the hot side on a socket on the case back ... it uses a power cord like the standard PSU cord; there are 2 power cords on the back in other words.

The fans for the radiator are hard wired into the same Molex connector that operates the relay. This makes the connection to the PSU. So when the relay is powered; the fans are powered.

Also, for WC maintenance, I move the 110 VAC connection for the pump from N/O to N/C. So when the power cord for the pump is plugged in ... the pump turns on without the computer powered up or even there. Works really well for getting the WC system up before even the mother board or PSU is added to the case == a very good thing. I always meant to wire in a little switch to make this more convenient, but never got to it.

I use Eheim 1040 pumps (2 different computers). They are at least 7 years old as they were used in previous dual Athlon MP systems & were rarely turned off & severely overclocked (for them at least).

The pumps are mounted behind the case power switch from the front ... this is behind the smaller expansion drive bay cage from the side. Pumps are held in place with a large square of velcro & a tye wrap.