As many of you are aware, the Biocube 8 is very prone to premature fan failure and the fans are LOUD. As it turns out, this seems to be due to a major design flaw in the biocube
One of the bearings on one of the stock fans in my Biocube failed, so I bought two 50mm Evercool brand fans to replace them.
The hinges are easy to disassemble - just use a flat screwdriver to pull out the hinge pins.

I opened the cover to reveal the stock fans:

I cut the wires and spliced them to the new fans - the yellow wires are for speed sensing and remain unused in this mod. Note: there are two different types of screws - this is because the mounting holes on the fans are recessed on one side, and the fans are in opposite orientations, so one set of screws needs to be longer.

I insulated the splices with electrical tape and tidied up the wires:

I put everything back together, turned the power on, and the new fans were EVEN LOUDER than the stock fans!
So, I took everything apart again, tried wiring a potentiometer in series with the fans to adjust the speed, which worked, but in doing so I realized the power supply is feeding over 19V to the fans rated at 12V!


The solution?
Wire the fans in series, instead of in parallel.
To clarify, the wires coming from the stock connectors to the fans are in parallel. I verified this with the multimeter.
I spliced both red wires together, both black wires together, and connected the fans in series. This led to a potential of 8.3V across each fan while in operation, and a relaxed din that sounds like it will last for a long time. There is still plenty of air flow, with room temp air going in one vent and warm air coming out the other.


One of the bearings on one of the stock fans in my Biocube failed, so I bought two 50mm Evercool brand fans to replace them.
The hinges are easy to disassemble - just use a flat screwdriver to pull out the hinge pins.

I opened the cover to reveal the stock fans:

I cut the wires and spliced them to the new fans - the yellow wires are for speed sensing and remain unused in this mod. Note: there are two different types of screws - this is because the mounting holes on the fans are recessed on one side, and the fans are in opposite orientations, so one set of screws needs to be longer.

I insulated the splices with electrical tape and tidied up the wires:

I put everything back together, turned the power on, and the new fans were EVEN LOUDER than the stock fans!
So, I took everything apart again, tried wiring a potentiometer in series with the fans to adjust the speed, which worked, but in doing so I realized the power supply is feeding over 19V to the fans rated at 12V!


The solution?
Wire the fans in series, instead of in parallel.
To clarify, the wires coming from the stock connectors to the fans are in parallel. I verified this with the multimeter.
I spliced both red wires together, both black wires together, and connected the fans in series. This led to a potential of 8.3V across each fan while in operation, and a relaxed din that sounds like it will last for a long time. There is still plenty of air flow, with room temp air going in one vent and warm air coming out the other.







