Internal Pump as External? Tested

[8BALL_99]

Well I did this cause of another thread about the question.. I've read, even been asked/told a couple thousand times that if you run a Internal water cooled pump like a mag or Eheim it will heat the water less.. I've always said I didnt' think it would since its a water cooled pump.. But at the same time I thought well maybe it will help a little.. Anyway I figured I'd give it a try to see for myself!

I tested a Mag12 both External and Internal. The test was done in a little less then 4 gallons of saltwater in a 5 gallon bucket. Also my Pump wattage might be a little on the high side.. My watt meter reads a little high.. It reads a constant wattage though..

External Test-------------------------------Internal Test
Saltwater @ 1.025------------------------Saltwater @ 1.025

Start 7:07pm-------------------------------Start 12:38am
Water Temp 75.7---------------------------Water Temp 75.5
Pump Case Temp 79-----------------------Pump Case Temp 80
Room Temp 75------------------------------Room Temp 75
Pump Wattage 191Watts----------------Pump Wattage 190

8:07pm-----------------------------------------1:40am
Water Temp 81.9-----------------------------Water Temp 82
Pump Case Temp 98-------------------------Room 75
Room 75----------------------------------------Pump Wattage 192
Pump Wattage 194

9:07pm-----------------------------------------2:40am
Water Temp 86.6-----------------------------Water Temp 86.1
Pump Case Temp103-------------------------Room 75
Room 75-----------------------------------------Pump Wattage 192-193
Pump Wattage 194

10:07pm----------------------------------------3:40am
Water Temp 90.1------------------------------Water Temp 88.9
Pump Case Temp 104-------------------------Room 75
Room 75------------------------------------------Pump Wattage 194
Pump Wattage 194

11:07pm
Water Temp 92.7
Pump Case Temp 105
Room 75
Pump Wattage 197

12:07am
Water Temp 93.5
Pump Case Temp 105
Room 75
Pump Wattage 196

I didnt' bother testing more then 3 hours on the Internal It was getting late and as you can see pretty much The Exact same tempiture increase anyway.. Only difference is that the pump seemed to pull a few more watts External as it heated up faster..

I still plan on Testing a Eheim but I have a feeling the results will be the same.. IMO/IME mounting a Water cooled Internal pump as a External pump doesn't do anything but make it louder...

Will

 

[Nitroq2]

Interesting, Thanks Will that information is helpful.
Judging by those times it looked more early than late WOW I thought I didn't sleep.

 

[Tomoko Schum]

Great information, 8Ball! Thank you for posting the results. It's kind of scary to see such a temperature rise (17.8 degrees) in just 5 hours. In a larger tank the rise should not be as much, but you can tell that a large pump is quite a heat source.

Tomoko

 

[8BALL_99]

lol Np, yeah 4 is about my cut off.. Most of the time I try to go to bed 12-2 but I dont' always make it hehe.

Tomoko your right, Well and you have to keep in mind this was in my Equipment room.. Even though the tempiture is 75 it really feels much cooler in the room and has a ton of air flow. If this was in a semi closed off stand. I think the temps would have went much higher much faster. I thought it was interesting too that once the pumps temp got above 85 it pulled another 4 watts.

Will

 

[Tomoko Schum]

Interesting. I suppose that heat can affect the efficiency of some electrical equipment.

I am keeping the house temp to 76 - 77 lately, but my tank temp is consistently at 82. It was right at 80 before I added a Kolaria 4 and another small PH with my Phosban reactor.

If an Eheim pump (equivalent to Mag12) runs a lot cooler than Mag12, I will switch my return pump to an Eheim pump for sure. (Hope you do the trial soon )

Tomoko

 

[8BALL_99]

The only problem the largest Eheims I have are 1260s,,, I think anyway. The Eheim 1262 would be more like a mag12.. I'm also kicking around ideas to check realworld GPH.. My mag 7 is rated a little higer then my Eheim 1260, But I know the Eheim moves more water, or atleast I think it does.. I'm sure a 1262 and a mag 12 would probably be pretty dern close if tested..

I thought about maybe pumping 30 or so gallons from a trough to another one or maybe a trashcan with about 5 foot of head.. Then just timing it with a stop watch.. Do it a couple times then just figure the average GPH.. How accurate do you think this would be for Testing GPH.. I would offcourse use the exact same plumping with each pump.

 

[fishdoc11]

Nice idea.
It would be interesting to run the test with a fan on the external pump. It would also be interesting to test a couple of true external pumps (one built for flow and one built for head pressure for example) that are fan cooled.

Chris

 

[8BALL_99]

I thought about a fan blowing onto the pump. It was even suggested in another thread. Someone even mentioned adding a heatsink/fan like on a cpu. But I'm kind of in the thinking if you want a aircooled external pump you would be better off buying one built for this. IMO my external test gave the pump an advantage cause my fish room has a Ton of airflow and is pretty small with its own AC. I might give it a try after I test the others just to see. Maybe with the Eheim.. I really don't see to much reason to go out of your way to use a mag External.. They are much louder mounted this way.. They aren't quiet pumps to begin with.

I might check if anyone has any small External pumps to test. The only ones I have are on my closed loops and the smallest one is 3600GPH.. Much bigger then an average Return pump. I would be happy to do the test.

 

[buzzbait00]

Thanks Will!Answered alot of my ?'s