Automate Your Air Conditioner with ESP32 and MQTT

11.12.2024 - Engine: Gemini

Materials:

• ESP32 module
• Temperature sensor (e.g., DHT22)
• Relay board
• AC appliance (e.g., air conditioner)
• MQTT broker (e.g., Mosquitto)

Steps:

Hardware Connection:

1. Connect the temperature sensor to the ESP32 (e.g., using I2C or GPIO).
2. Connect the relay board to the ESP32 (e.g., using GPIO).
3. Connect the AC appliance to the relay board.

Software:

1. Install required libraries:

   • Arduino IDE: ArduinoJSON, PubSubClient
   • PlatformIO: $ pio pkg install adafruit/DHT

2. Create the ESP32 sketch:

   • Import the libraries.
   • Define the GPIO pins for the temperature sensor and the relay.
   • Initialize the temperature sensor and the MQTT client.
   • Read the room temperature in a loop.
   • Publish the temperature to the MQTT topic /room/temperature.
   • Subscribe to the topic /room/setpoint.
   • When a target temperature is received, store it and control the relay accordingly.

3. Configure MQTT broker:

   • Create topic /room/temperature to receive temperature data.
   • Create topic /room/setpoint for sending target temperature.

Usage:

1. Compile and upload the ESP32 sketch.
2. Connect the ESP32 to the MQTT broker.
3. Use an MQTT client (e.g., MQTT.fx) to publish the target temperature to the topic /room/setpoint.
4. The AC unit will now be controlled automatically to maintain the room temperature at the set target temperature.

Additional Features:

• Manual control: Provide manual buttons or a display to set the target temperature.
• Timer: Implement timed control of the AC unit.
• Remote access: Use a cloud service to enable control from anywhere.