Arduino-based replacement fan controller for the Levoit LV-PUR131 air filter.
After six years, the control board in one of my Amazon-bought Levoit LV-PUR131 air filters finally failed. Seeing as I don't use most of its features and only use it for low/medium/high constant-on, I figured I'd just make a replacement fan controller using a 4-position rotaty switch. Unfortunately it's a PWM-controlled fan, so it required an Arduino too.
- fan_controller_rotary_with_fuses_caps.pdf - PDF schematic and wiring info for breadboard testing (ChatGPT / GPT5 generated)
- levoit-LV-PUR131-fan-controller.ino - Arduino sketch to control the fan based on a 4-position (off/low/medium/high) rotary switch input (ChatGPT / GPT5 generated)
