A simple UI to control a fan in a lotus grill with an esp8266 with arduino interface. The chip creates an access point (AP) and uses a captive portal to provide easy access to the UI.

UI

The UI provides the following actions:

1. Turn the fan on/off
2. Set the speed of the fan
3. View the connection status to the server

Peripherals

There is a 5V DC brushless motor fan connected to a transistor. The arduino switches the transistor with 3.3V which connects GND and GND of the fan. It uses PWM to control the speed of the fan.

Problems

• The fan rpm is not linear to the speed selected in the UI.
• The fan makes buzzing sound at some low speeds