Hotend Fan Mysteries: Always On? Ender 3 Insights & Beyond!

Having your hotend fan continuously operational can certainly disturb the peace, especially if you’ve strategically placed your 3D printer right in your room, dreaming of some silent nights. Being the tech trainee that I am, Carolina, I couldn’t resist diving deep into this to quench our collective curiosity. So, should you let that hotend fan sing its uninterrupted tune? And if you fancy a pause, how does one achieve that for a popular model, say, the Ender 3?


Understanding Your Hotend Fan
Your hotend typically boasts two fans. One dedicated to part cooling and the other to heatsink cooling. The essentiality of the heatsink cooling fan cannot be overstressed; its role is pivotal. Ignoring it could lead the filament within the heat sink to cool down prematurely, potentially resulting in an undesired clog.

Once your print job comes to a conclusion, the fan diligently works its magic to temper the hotend housing the filament. Prematurely silencing this fan might inadvertently usher heat upwards, compromising the filament and setting the stage for an inevitable jam. Imagine the ordeal of clearing the hotend to make it ready for your next print masterpiece!

Fans at the forefront, keeping your hotend at bay, are perpetually active. Their uninterrupted operation is courtesy of a steady 12V supply, devoid of any intermediary circuitry. This design decision isn’t arbitrary; it’s a safety measure deeply embedded into the printer’s design DNA, making it impervious to software or firmware tweaks.

Customize the Fan Operation
If the constant hum grates on your nerves, consider upgrading. A quieter alternative, like the Noctua NF-A4x10 Premium Quiet Fan, might be just what you need. But, remember, the Ender 3’s stock fan operates at 24V, so to harmonize the voltage levels, a buck converter might be necessary.

For the fans among us, it’s worth noting that one can program the hotend fan to power down once it descends to a comfortable temperature (around 50°C), using specific commands in your G-Code. Tread this path only if you’re well-acquainted with the nuances of 3D printing.

Turning Off the Extruder Fan on Ender 3
To safely switch off the extruder fan:

1. Power Down the Ender 3: Begin by allowing the hotend to cool sufficiently post print, then power down your Ender 3. For the uninitiated:
– Navigate to “Prepare”
– Select “Cooldown”
– Patiently wait for the cooldown to culminate
– Finally, power off your printer

2. Implement a Tailored External Circuit: This involves introducing a DIY circuit within the fan wires, one that monitors temperature. This technique essentially harnesses temperature readings to decide the fan’s operational state. The underlying principle here is simple: a dip in the thermistor’s temperature results in resistance elevation, consequently affecting the voltage and, in turn, the fan.

3. Parallel Wiring with Other Fans: This method entails wiring the extruder fan parallelly with the part cooling or other fans, allowing you to tweak its settings in the firmware akin to the other fans on the Ender 3. Before you proceed, ensure you’re guided either by an expert or a reliable technical video detailing the steps.

Amplifying Your Ender 3 Capabilities
Beyond the fan dynamics, there’s so much more to explore with the Ender 3. From enhancing its dimensions with the Ender Extender to understanding the intricate differences between Ender-3 Neo, Ender-3 V2 Neo, and Ender-3 Max Neo, the possibilities are as limitless as your imagination. Dive in, explore, and let your creativity soar!