DDC non-starting issue resolution thread

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Originally Posted by _G_

crap, looks like i got a bad one too:rolleyes: mfg 7/06
was working fine when was leak testing, sat a month dry while waiting for a mobo rma. now the impeller just twitches back and forth.

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Have you taken it apart? The impeller assembly just sits on top of the ceramic bearing. Pretty strong magnet so you must use a little force. Check that there is no dried gunk impeding the rotation.

http://img237.imageshack.us/img237/7...xplodedll6.jpg

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Originally Posted by RickH

The latest versions of SpeedFan allow you to set up events that execute under certain conditions. I've got one that shuts down the system if the pump RPMs are too low, and a backup that also shuts down if the CPU temp is dangerously high. It's free insurance.

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nice one, thanks a lot for the tip :thumbsup:

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Originally Posted by SiGfever

Have you taken it apart? The impeller assembly just sits on top of the ceramic bearing. Pretty strong magnet so you must use a little force. Check that there is no dried gunk impeding the rotation.

[SNIP][/SNIP]

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yep, took it apart and cleaned it. put it in a test loop and it did the same thing (plexi tops are good for situations like this:) ) then when i was trying to flick start it it completly died (smelled like fried circuit board) rma time:banana:

put a drop of glycerin on the ceramic berring, and add some propylen Glycol (This is the non toxic safe to drink type, though after tast is horrid so don't drink it, is sweet though) to the loop to help lubricate it and see if that helps.

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Originally Posted by Xeon th MG Pony

put a drop of glycerin on the ceramic berring, and add some propylen Glycol (This is the non toxic safe to drink type, though after tast is horrid so don't drink it, is sweet though) to the loop to help lubricate it and see if that helps.

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What was the DDC's application before PC water cooling enthusiasts got their hands on it?

If it was designed for 24/7 continuous operation, reliable starting may not have been a key design consideration that is obviously much more critical to water cooling PC's than it may be to it's original intended application.

I also agree with Xeon on the lubrication. It can't hurt. I had two bad pumps (both from Performance PC's :confused: ) that I found to be bad in the course of testing (where I was using just tap water). The MO for failure was an inability to start reliably quickly leading to a complete inability to start. Since I got my replacements (the went straight into the loop for water cooling duty - no testing or screwing around), I've run 10:1 distilled:Pentosin and I must say the Pentosin is a great lubricant - the coolant is slippery stuff. It also keeps the coolant from evaporating - spilt drops on my work bench will sit there for days until I wipe them up (although I suspect this property has nothing to do with helping/hindering pump reliability). So far, no issues starting reliably with the coolant (knock on wood) :hammer:

Is it possible some of these problems have been caused by the counterfeit pumps? Not all, but some?

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Originally Posted by Xeon th MG Pony

put a drop of glycerin on the ceramic berring, and add some propylen Glycol (This is the non toxic safe to drink type, though after tast is horrid so don't drink it, is sweet though) to the loop to help lubricate it and see if that helps.

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yep, it was running on 100% distilled, guess that might have had something to do with it

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Originally Posted by virtualrain

What was the DDC's application before PC water cooling enthusiasts got their hands on it?

If it was designed for 24/7 continuous operation, reliable starting may not have been a key design consideration that is obviously much more critical to water cooling PC's than it may be to it's original intended application.

I also agree with Xeon on the lubrication. It can't hurt. I had two bad pumps (both from Performance PC's :confused: ) that I found to be bad in the course of testing (where I was using just tap water). The MO for failure was an inability to start reliably quickly leading to a complete inability to start. Since I got my replacements (the went straight into the loop for water cooling duty - no testing or screwing around), I've run 10:1 distilled:Pentosin and I must say the Pentosin is a great lubricant - the coolant is slippery stuff. It also keeps the coolant from evaporating - spilt drops on my work bench will sit there for days until I wipe them up (although I suspect this property has nothing to do with helping/hindering pump reliability). So far, no issues starting reliably with the coolant (knock on wood) :hammer:

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looks like I may have to make a trip to the Audi dealership for some Pentosin

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Originally Posted by Kayin

Is it possible some of these problems have been caused by the counterfeit pumps? Not all, but some?

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not in my case (mine was a real one from DD)
link to story
http://www.nokytech.net/attention_de...g_-5434-a.html

Interesting.

I drew the correlation from the advent of fakes to this, but this is altogether different. It does seem to be some type of "24/7" issue, in which it wasn't expected to turn on and off all the time... but I could be talking out of my ass. Pump design, at least, I have no ideas on. Just conjecture and speculation ATM...

I'm not sure but I think the DDC was designed for computer use? For those watercooled macs? Could be wrong though.