im planning my next set up.everytime ive added a pump to my sump im always turning down the flow with a ball valve. it seems to me it would cause more pressure on the pump and cause heat issues. i want to run vortechs to help with heat and if a pump is a little oversized and turning it down causes heat im really trying to avoid that.any one ever test this?
does turning the flow down on apump cause more heat?
- Thread starter markl
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I believe whether heat is lessened depends on the pump drive type.
Reducing the outflow of a submersible mag drive type pump (Mag drive/Eheim/Rainbow Lifegard) causes the pump to draw less wattage. This type pump rotates the electricity around a motor coil and causes the magnetic impeller assembly to spin.
Same for a Reeflo/Sequence/Dolphin type drive pump. Reduce the output and it draws less wattage. This is the type of drive where there is an actual turning shaft connecting the motor to the pump head. You can usually view the turning shaft, as it is the only thing connecting the motor to the pump head.
This is not the case for Iwaki/Pan World/Velocity type pumps. These type drive systems turn a magnetic bell housing attached to the motor, which then causes a sealed magnet/impeller to turn in the pump head. Reduce the output and the wattage draw is the same.
The Iwaki types probably use the same wattage because the motor bell housing assembly probably spins at the same speed regardless of the output of the pump, whereas the other two drive types use less energy because the motor slows down as the output is decreased. Reeflo drives are directly attached to the impeller, and decreasing output means decreasing motor RPMs.
Not sure of the physics behind the mag drive types using less wattage, but I would guess that there is less wattage draw because as you decrease output the magnet/impeller assembly spins less, and it causes the motor coil to not rotate the electicity around the motor coil as fast, thus using less wattage.
I think the Iwaki type pumps would have about the same heat produced regardless of the lessening of the output because they draw the same wattage, but you would probably have less heat with a Reeflo or Mag drive type pump because these two pump drive systems use less wattage as the outflow is reduced.
I asked a similar question several weeks ago and actually tested the three pump types with a Kill-a-Watt. Read the thread here:
Reducing the outflow of a submersible mag drive type pump (Mag drive/Eheim/Rainbow Lifegard) causes the pump to draw less wattage. This type pump rotates the electricity around a motor coil and causes the magnetic impeller assembly to spin.
Same for a Reeflo/Sequence/Dolphin type drive pump. Reduce the output and it draws less wattage. This is the type of drive where there is an actual turning shaft connecting the motor to the pump head. You can usually view the turning shaft, as it is the only thing connecting the motor to the pump head.
This is not the case for Iwaki/Pan World/Velocity type pumps. These type drive systems turn a magnetic bell housing attached to the motor, which then causes a sealed magnet/impeller to turn in the pump head. Reduce the output and the wattage draw is the same.
The Iwaki types probably use the same wattage because the motor bell housing assembly probably spins at the same speed regardless of the output of the pump, whereas the other two drive types use less energy because the motor slows down as the output is decreased. Reeflo drives are directly attached to the impeller, and decreasing output means decreasing motor RPMs.
Not sure of the physics behind the mag drive types using less wattage, but I would guess that there is less wattage draw because as you decrease output the magnet/impeller assembly spins less, and it causes the motor coil to not rotate the electicity around the motor coil as fast, thus using less wattage.
I think the Iwaki type pumps would have about the same heat produced regardless of the lessening of the output because they draw the same wattage, but you would probably have less heat with a Reeflo or Mag drive type pump because these two pump drive systems use less wattage as the outflow is reduced.
I asked a similar question several weeks ago and actually tested the three pump types with a Kill-a-Watt. Read the thread here:
In the books for mag pumps it says its best to restrict them a tad..
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Even if you restrict a pressure pump which Dave tested ,the watts did not increase. The majority of the heat produced is from the electric motor and is directly related to the amount of energy used ,expressed in watts. No a pump will not produce more heat if no more watts are used.
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The reason alot of the Iwaki, Panworld and velocity pumps do not reduce wattage with restriction is that they are pressure rated pumps. They are much stronger pumps than their low pressure brothers. A pressure rated Iwaki pushing 1100+ gph at 0' of head pressure is a 1/9 hp motor. The circulation rated Iwaki pushing 1100+ gph at 0" of head pressure is a 1/16 hp motor, almost half as much. An electric motor will only use X amount watts per revolution.So if you restrict the flow thereby restricting the rpm you use less watts which is easier to do on a lower hp motor(circulation rated) and more diffilcult to do on a higher hp motor(pressure rated).
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In the above post I was referring to Ac motors only. Also Some external pumps may fell a little warmer to the touch because the fan is not turning as many rpms as before restriction but I doubt it coulld very noticable.
