take a look at this pump

[Phextwin]

Um...I think zero flow means you’re operating at max head...right? And I think you mean “>8m”. And have you tried this?

Yes, zero flow is when you are at maximum head (correlates to the P-Q chart). Yes, >, you are correct. No i have not, unfortunatly i dont have an 8m tall ladder. Nor do i need to as there is no need to try this, as it is true. But if you really want me too i could do it with my little march 893-09.

Are you saying that a Mag 5 can’t physically pump 400 gallons of water? And if it can, then why can’t a Mag 3 pump 350?

I am unaware of the maximum flow capabilities of the Mag3 & 5, so i will assume they are rated for 350 & 400 GPH based off your statement. And yes, that is what i am saying. The pump housing and barbs themselves act as a restriction on the flow which, of course, lowers it.

 

[Graystar]

I am unaware of the maximum flow capabilities of the Mag 3 & 5

Ah, sorry. My mistake. The Mag 3 has a 0 head flow of 375 gph and the Mag 5 has a 0 head flow of 500 gph.

In any case, I think we've strayed too far from the original issue, which was how much heat is added to the water. Regardless of how head affects flow or any of the other things discussed, It is the BHP for the given rate of flow that will be imparted onto the water.

I don't have a BHP chart for your MD-30, but I'd guesstimate that it's putting anywhere between 25 to 45 watts of power into the water.

 

[Graystar]

i was going to reply to graystar, but realized that the only thing i was doing was flaming.

please don't preach about thermodynamics unless you understand it yourself.

sound is kinetic energy. dropping a box doesn't creat mainly heat energy....

i need to stop... i'm getting angry at you

Well...first, I didn't say it creates mainly heat. I said that it creates sound and heat and all the energy will turn into heat. Second, just do what I do...I put you on ignore and now I don't have to see your posts...problem solved!

 

[voigts]

Interesting discussion. Coming back however to the heat question, it seems to me that 20-30w of heat into a loop that has plenty of excess cooling capacity (like using a BIXIII or in my case a car rad with a decent Swifty type pump) is merely a "drop in the bucket" and wouldn't make a bit of difference in temps. I realize that there are a variety of issues here that come into play, but really when it is all said and done, I don't see 20-30w extra or so being much to worry about.

I think I'll stick to my 50z.

 

[Phextwin]

In any case, I think we've strayed too far from the original issue, which was how much heat is added to the water.

Quite a tangent indeed

I don't have a BHP chart for your MD-30, but I'd guesstimate that it's putting anywhere between 25 to 45 watts of power into the water.

About 46W. Which is pretty close to what it is rated for on the case. (45W)

 

[Graystar]

About 46W

Yikes! That's over half the amount of heat you're trying to get rid of in the first place! (sans oc, gpu, nb, and hd cooling)

I used to run a March 893-04...the brushed submersible model. It lasted well past it's 5000 hr rating, but it didn't last an entire year. Wish I had an -09...those are awesome! But I got mine for 25 bucks on ebay, so I can't complain. Better than $160! Those suckers are pretty darn efficient.

So are we now going to calculate how much heat that siphon pump would add to the water?

 

[Graystar]

I think I'll stick to my 50z.

Well, with a 50 I'd guess it's just like cooling a dual processor machine...so you may be right.

 

[Phextwin]

Yikes! That's over half the amount of heat you're trying to get rid of in the first place! (sans oc, gpu, nb, and hd cooling)

Thats why my rad is a veritable bohemoth. It is the main rad of a family sedan (XF falcon)

I used to run a March 893-04...the brushed submersible model. It lasted well past it's 5000 hr rating, but it didn't last an entire year. Wish I had an -09...those are awesome! But I got mine for 25 bucks on ebay, so I can't complain. Better than $160! Those suckers are pretty darn efficient.

I havn't really played with mine much unfortunatly. But it is a very nice unit.

So are we now going to calculate how much heat that siphon pump would add to the water?

I'll leave that to someone who isn't me thankyou very much

 

[tdsfan]

I had one of those that was designed for water.. if it runs dry for say 30 seconds it just melts.