Dual pump position

GTXnexus

New member
Hi guys

So normally when we have two pumps in serial we theoretically double the head pressure in order to overcome restriction in the loop. My question here is that do I have to connect one pump right after the other to get the above benefit?

example1: reservoir>>pump1>>pump2>>rad1>>rad2>>block1>>block2>>reservoir
(since that's the way how dual pump tops are configured, it should be workable)

example2: reservoir>>pump1>>rad1>>block1>>rad2>>pump2>>block2>>reservoir
(so this is what I'm trying to figured out. Basically all the other situations where pump2 is placed anywhere else other than straight after pump1. Do these types of configurations work the same way as example1?? Thanks...:):)
 
I wouldn't have anything but a res or another pump, feeding the inlet for a pump. (personally)
 
I doubt youll ever need two pumps dude - Ive got a LOT of stuff in my loop and my D5 pump is turned down to 2 out of 5!
 
I doubt youll ever need two pumps dude - Ive got a LOT of stuff in my loop and my D5 pump is turned down to 2 out of 5!

Thanks for the reply

Since I have 3 gpu blocks, a cpu block, a 480rad, a 360rad and a 240rad all in one big loop and I've got a spare pump so I thought I might just throw that in as well. And that's where the question in the OP come from. Even though one D5 might get the job done, it's always interesting to know how it works. Back to that question, any ideas?? Cheers..:)
 
It won't make any difference in what order you place them. Just do whatever makes the loop neatest. Obviously it goes without saying that you need to keep them in a position where the loop can be filled above them before they are powered on.

JR
 
It won't make any difference in what order you place them. Just do whatever makes the loop neatest. Obviously it goes without saying that you need to keep them in a position where the loop can be filled above them before they are powered on.

JR

Thanks for the reply

So I guess I'll just use the pump fed by reservoir to fill the loop and then power on the other pump afterwards

Since I have 3 gpu blocks, a cpu block, a 480rad, a 360rad and a 240rad all in one big loop now, will it be a better idea that I split them into 2 loops? I know its kind of overkill but it just feels good that the case is full, haha... Also benefits and drawbacks on single vs dual loops?? Cheers...:)
 
Thanks for the reply

So I guess I'll just use the pump fed by reservoir to fill the loop and then power on the other pump afterwards

Since I have 3 gpu blocks, a cpu block, a 480rad, a 360rad and a 240rad all in one big loop now, will it be a better idea that I split them into 2 loops? I know its kind of overkill but it just feels good that the case is full, haha... Also benefits and drawbacks on single vs dual loops?? Cheers...:)

A single loop is more efficient as it allows use of all of the available radiator space for whatever components need it the most so it will naturally deal with the heat load in the best way possible. A single loop with serial pumps would also give you some redundancy, if one pump fails the other will keep the loop flowing.

The big advantage of dual loops is just the inherent fact you can drain and replace components in one of the loops. If you were changing CPU or GPU frequently it would be helpful to leave the other loop undisturbed. Although for most people who change CPU's less often than their underpants that isn't really going to help anything as it's just as much effort to drain a small loop as a big loop. I suppose it's also worth considering that you would need two reservoirs, more fittings and more tubing so it does add a little cost and complexity.

JR
 
Single loop > dual loop. Just stick with one nice big tidy run, will be far superior :)
 
A single loop is more efficient as it allows use of all of the available radiator space for whatever components need it the most so it will naturally deal with the heat load in the best way possible. A single loop with serial pumps would also give you some redundancy, if one pump fails the other will keep the loop flowing.

The big advantage of dual loops is just the inherent fact you can drain and replace components in one of the loops. If you were changing CPU or GPU frequently it would be helpful to leave the other loop undisturbed. Although for most people who change CPU's less often than their underpants that isn't really going to help anything as it's just as much effort to drain a small loop as a big loop. I suppose it's also worth considering that you would need two reservoirs, more fittings and more tubing so it does add a little cost and complexity.

JR

Thanks again for the info, I think I'll stick with one big loop and get some of those quick disconnect fittings instead if I plan on changing parts
 
Single loop > dual loop. Just stick with one nice big tidy run, will be far superior :)

Thanks bro, making it easier for me as I've got everything in hand to throw that bad boy in the loop and get it up and running instead of placing an order and wait for days...:)
 
If I were to add one suggestion, then it would be to get a double pump top for both your D5s. That way you know that both pumps are getting fed coolant correctly, and they look awesome too.
 
If I were to add one suggestion, then it would be to get a double pump top for both your D5s. That way you know that both pumps are getting fed coolant correctly, and they look awesome too.

Thanks for the input. Not sure if I'm following though. Would you mind elaborating on how pumps might not be fed correctly in those types of setups(I mean without a dual pump top and not placing them one right after the other)?
 
The recommendation is that each pump is fed from a reservoir or directly from an adjacent pump, to prevent any air reaching the impeller. if you have any components between the pumps, there's a possibility that trapped air could get into pump 2, and that can be fatal for the impeller which requires to be completely immersed in coolant at all times. Seeing as you're going to mount the pumps next to each other, the most aesthetically pleasing solution to do that is to use a dual pump top.

This is the sort of thing I'm talking about, and you can see it takes the output from pump 1 directly into the input of pump 2, without any convoluted pipe runs or fittings...

ex-pmp-186.jpg
 
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A single loop is more efficient as it allows use of all of the available radiator space for whatever components need it the most so it will naturally deal with the heat load in the best way possible. A single loop with serial pumps would also give you some redundancy, if one pump fails the other will keep the loop flowing.

The big advantage of dual loops is just the inherent fact you can drain and replace components in one of the loops. If you were changing CPU or GPU frequently it would be helpful to leave the other loop undisturbed. Although for most people who change CPU's less often than their underpants that isn't really going to help anything as it's just as much effort to drain a small loop as a big loop. I suppose it's also worth considering that you would need two reservoirs, more fittings and more tubing so it does add a little cost and complexity.

JR

There it is.

/thread.


Dual loops are for Multi CPU/Multi GPU with thermally sensitive OC's.

And showoff's.

Pump power in general,like rad space, is massively over estimated.
 
I have 2 D5's and one thing I did not really think about is noise. Even on 2, if your case is almost beside your ear, i can be audible over the fans if you keep those running at less than 800RPM.
 
now wait a sec rad space is not overestimated lol.
The more space you have the quieter you can have your fans.
and there is a balance where you have to have a minimum ammount of rad space for what you are cooling.
(you wont be cooling a overclocked q6600 on a 80mm rad for instance)

the flow rate is however less of a issue. aslong as fluid is getting back in to the res and the coolant isnt staying in the block so long as it is no longer absorbing heat efficiently then the flow rate is plenty. and this is actually not that fast either..
i can manage 480 + 360 + 240 rads "with what is probably close to 10 feet of tubing" Using 90 degree elbow fittings and a tight ark of tubing to connect 2 of the rads. with a gpu block and a cpu block with 1 pump. And im thinking i am at about where this pump can be happy working.

As for having 2 pumps.
You can have the second one ANY where you like. PROVIDED you dont connect it to the power before you fill the loop
you have to have water fully returning to your res before you can turn the second pump on.
It is better to have it as close to the 1st pump as possible. Preferably below it because gravity can still feed it just like gravity feeds the 1st one.
 
now wait a sec rad space is not overestimated lol.
The more space you have the quieter you can have your fans.
and there is a balance where you have to have a minimum ammount of rad space for what you are cooling.
(you wont be cooling a overclocked q6600 on a 80mm rad for instance)

the flow rate is however less of a issue. aslong as fluid is getting back in to the res and the coolant isnt staying in the block so long as it is no longer absorbing heat efficiently then the flow rate is plenty. and this is actually not that fast either..
i can manage 480 + 360 + 240 rads "with what is probably close to 10 feet of tubing" Using 90 degree elbow fittings and a tight ark of tubing to connect 2 of the rads. with a gpu block and a cpu block with 1 pump. And im thinking i am at about where this pump can be happy working.

As for having 2 pumps.
You can have the second one ANY where you like. PROVIDED you dont connect it to the power before you fill the loop
you have to have water fully returning to your res before you can turn the second pump on.
It is better to have it as close to the 1st pump as possible. Preferably below it because gravity can still feed it just like gravity feeds the 1st one.

You can get away with far less rad space than most people spec for their requirements and still maintain a decent delta.
The rule of thumb of 240 then 120 for each block provides a good balance but you can go much below that and retain a good cooling v noise ratio.

I agree with your pump comments however.
 
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