Using the small LOLIN D1 mini, a Oled shield and a sensor breakout board, its possible to get a sense of CO2 in the air.
Sends both eCO2 ans TVOC.
For example to use with Hass.io [link]
The Oled screen is optional and can be disabled in the settings.
front:
back:
- ESP8266 (Wemos/LOLIN D1 mini)
- SGP30 eCO2 sensor
- Basic soldering and wiring skills
- OLED Shield (Wemos/LOLIN 64x48 I2C)
- Oled library [link]
- SGP library [link]
- Arduino IDE / VS Code
- (For Wemos d1 mini) CH340G driver [link]
The oled shield fits exactly on the ESP, so no other connections are required.
| ESP8266 | SGP30 |
|---|---|
| 3.3v | VCC |
| GND | GND |
| D1 | SCL |
| D2 | SDA |
Copy Settings.example.h to Settings.h and fill in the correct data.
| Setting | default | Description |
|---|---|---|
| WIFI_HOSTNAME | C02Logger | device name on network |
| WIFI_SSID | - | Wifi name to connect to |
| WIFI_PASSWORD | - | Wifi password |
| MQTT_HOST_NAME | - | MQTT broker address |
| MQTT_PORT | 1833 | MQTT broker port |
| MQTT_USER_NAME | - | MQTT user name |
| MQTT_PASS | - | MQTT password |
| MQTT_TOPIC | co2meter | MQTT topic prefix |
| MQTT_UPDATE_INTERVAL | 30000 | Send interval (ms) |
| SENSOR_MEASUREMENT_FREQUENCY | 5000 | Sensor update interval (ms) |
| USE_SCREEN | true | Enable or disable screen |
| SHOW_CONNECTION_STATUS | true | Show wifi and MQTT status |
| DEBUGE_MODE | true | Debug mode |
Subscribe to co2meter/<topic> in your MQTT client. prefix can be changes in the settings.
| Topic | Description | Unit |
|---|---|---|
| eco2 | eCO2 value | ppm |
| tvoc | TVOC value | PPB |