ESP32-S2 WiFi Fan Controller for Home Assistant - 4x PWM, Made for ESPHome

Made for ESPHome Certified

Officially certified under the Made for ESPHome program. Plug in, connect to WiFi via the captive portal, and Home Assistant discovers it automatically - zero manual configuration.

4-Channel Smart Fan Control

An ESP32-S2-based WiFi fan controller compliant with EU Radio Equipment Directive (CE RED) that gives you independent PWM control over up to 4 fans with built-in temperature and humidity sensing. Runs ESPHome firmware with native Home Assistant integration - auto-discovery, dashboard control, and automations out of the box.

Perfect for cooling server racks, network cabinets, NAS enclosures, 3D printer chambers, grow tents, or any setup where you need smart, quiet fan control.

Features

• 4x Independent PWM Fan Control - 25 kHz PWM per channel, each fan from full stop to 100%
• Built-in HDC1080 Sensor - temperature and humidity monitoring on the board
• RPM Monitoring - individual tachometer readout per fan (5V open-collector, pulled up on-board)
• RGB Status LEDs - per-fan NeoPixel LEDs, fully customizable
• Qwiic/I2C Expansion Port - 3.3V logic, add external sensors, displays, or peripherals
• 5V NeoPixel Output - drive additional LED strips
• 3 User Buttons - programmable for custom functions
• GPIO Expansion Pads - 2.54mm SMD header for custom wiring
• USB-C - for programming and initial firmware flash
• 12V DC Barrel Input - 5.5x2.1mm, supports up to 2.5A combined fan draw

Compatible Fans

Any standard 12V 4-pin PWM fan: Noctua NF-A12x25, NF-F12, NF-A14; Arctic P12 PWM, P14 PWM; be quiet! Silent Wings 4. Designed for 12V fans only. 3-pin fans are not supported.

Note: most PWM fans have a minimum duty cycle below which they stop spinning (typically 15-20%). ESPHome exposes this as a configurable minimum - see the documentation for per-fan tuning.

Smart Home Integration

Ships pre-flashed with ESPHome factory firmware. Connect to the 2.4 GHz captive portal WiFi hotspot, enter your credentials, and Home Assistant discovers it automatically. Supports PID control, linear fan curves, and fully custom automation via ESPHome YAML. Over-the-air (OTA) updates via WiFi after initial setup.

Why buy instead of build?

The firmware and schematics are open. You can read exactly how it works, fork the ESPHome config, and study the design on GitHub. If you want the hardware, this is where you get it.

What you're paying for:

• Assembled and tested - every board powered up, all 4 channels verified
• Firmware pre-flashed - ESPHome config tuned for common fan models, captive portal ready
• CE certified - RED 2014/53/EU compliance testing done
• Revision 3.3 - iterated through real-world issues so you don't have to
• Supported - if something doesn't work, there's someone to email

Open Source

ESPHome firmware configs and hardware schematics on GitHub: github.com/zeroflow/esphome-fancontroller

Documentation & Resources

Full documentation, setup guides, pinout reference, and wiring diagrams: fancontroller.arthofer.dev

3D printable case: Printables.com

Shipping & Support

For EU customers: select DDP Economy Express at checkout - VAT is included, no customs handling required, delivered to your door. Other shipping options may require you to clear VAT/customs yourself.

Sold by Arthofer Engineering e.U. (Vienna, Austria). Includes 2-year EU statutory warranty. Support via fancontroller.arthofer.dev.

Specifications

• MCU: ESP32-S2
• Input: 12V DC, 5.5x2.1mm barrel jack, reverse polarity + resettable fuse protection
• Fan outputs: 4x 4-pin PWM (Molex 47053-1000), 25 kHz PWM frequency
• Max combined fan current: 2.5A (shared across all 4 channels)
• Tachometer input: 5V tolerant, open-collector with on-board pull-up
• Sensor: HDC1080 (temperature ±0.2°C, humidity ±2%)
• Connectivity: WiFi 802.11 b/g/n, 2.4 GHz only (ESP32-S2 limitation)
• Expansion: Qwiic/I2C (3.3V), 5V NeoPixel output, 2.54mm GPIO header
• Programming: USB-C + OTA via WiFi
• Compliance: CE (RED 2014/53/EU)
• Dimensions: 70mm x 45mm x 15mm
• Origin: Designed and certified in Austria