@Optimus
On my K2 Plus a fan stay on no matter how long the printer has been at idle… even hours later. The fan is loud, I suspect it is the power supply fan since the fans for model, side, back are all off.
Is this a firmware bug or Creality Print slicer bug?
thx
Most definitely PSU fan. I have 6 printers from 3 manufacturers and all of them the PSU fan stays on all the while the printer is on, even at idle. I have increased fan size on a couple of printers to make them quieter but that is about all you can do.
In my case I just replaced the PSU fan with a standard silent 60x14 fan from noctua, works great if you know what you are doing. Saves a lot of noise.
Hi, sounds nice, my fan is also loud. I can only find this varites of noctua:
NF-A6x15 12V PWM 4-pin
NF-A6x15 12V FLX 3-pin
NF-A6x15 5V PWM 4-pin
NF-A6x15 5V 3-pin
Do you know what variant it should be?
Thanks in advance!
Unless you want to mess with DC-DC converters to step down the voltage from 24V to 12 or 5V, none of the fans you have listed will do. Let me explain:
Your printer’s PSU is 24V (older printers used to have 12V PSU) so you need to match the voltage of the components you want to use, with the voltage yiur PSU provides or use an electronic board to change the voltage from the PSU to the voltage the fan requires (also known as buck converters)
Hope that helps
For the PSU internal fan, it is a 12v fan. The NF-A6x15 12v FLX 3-pin is what I installed. You have to open up the PSU itself.
As the next post says, all other fans within the printer are 24v fans, which are much harder to replace.
I didn’t know that so I stand corrected and thank you for sharing 
Is this a direct swap or are there any modifications needed? my PSU fan gets very loud at times like if it had a bearing problem. I’ve been trying to find any information on this and I cannot find anything.
It is almost a direct swap, granted that you know how to crimp a set of jst connectors on a wire. From the fan you need to replace the three pin standard fan connector, to the new connector a two pin jst. I do not remember it was a 2mm pitch or a 2.54mm pitch version of the connector, since I have both of them lying around, I just picked the matching ones. So make sure to measure them beforehand to make sure a jst-xh or jst-ph is needed.
Of course, you could also use those omricon connectors which are always part of a noctua delivery. I have no experience with them, but they are specifically made for these situations.
Other than that, no modification were needed.
Is there room for a 25mm fan or only 15mm?
No, only 15mm or less.
The airflow would be blocked using a thicker one, even if it could fit.