會議室愈坐愈悶？阿明博士用 SCD41 看懂通風變化

範例明確關閉自動自我校正 ASC，讓讀者先依使用空間評估校正方式。這不代表關閉就一定更準；日常是否會接觸符合條件的新鮮空氣，會影響 ASC 是否適合。關閉後，一樣要安排比對與維護。

不要對著感測器吹氣後，就把它強制設成 400 ppm。強制校正需要穩定、已知的參考濃度和原廠要求的運作條件，不能用隨手量到的數字代替。

esphome: name: course-02-scd41 friendly_name: "SCD41 通風提醒" min_version: 2026.10.1 compile_process_limit: 1 esp32: board: esp32-s3-devkitc-1 flash_size: 16MB framework: type: esp-idf psram: mode: octal speed: 80MHz logger: hardware_uart: USB_SERIAL_JTAG level: DEBUG wifi: ssid: !secret wifi_ssid password: !secret wifi_password power_save_mode: none reboot_timeout: 0s ota: - platform: esphome password: !secret ota_password web_server: port: 80 version: 3 local: true auth: type: digest username: !secret web_username password: !secret web_password i2c: id: sensor_bus sda: GPIO8 scl: GPIO9 scan: true frequency: 100kHz external_components: - source: type: local path: components components: [sht20_local] sensor: - platform: sht20_local id: sht20_driver address: 0x40 update_interval: 10s temperature: id: sht_temperature name: "SHT20 Temperature" on_value: then: - lambda: |- id(last_sht_ms) = millis(); id(sht_seen) = true; humidity: id: sht_humidity name: "SHT20 Humidity" on_value: then: - lambda: |- id(last_rh_ms) = millis(); id(rh_seen) = true; - platform: scd4x id: scd41_driver address: 0x62 measurement_mode: periodic # Enable ASC only after evaluating the actual fresh-air exposure pattern. automatic_self_calibration: false update_interval: 10s co2: id: co2_value name: "SCD41 CO2" on_value: then: - lambda: |- id(last_co2_ms) = millis(); id(co2_seen) = true; temperature: name: "SCD41 Internal Temperature" humidity: name: "SCD41 Internal Humidity" globals: - id: last_sht_ms type: uint32_t restore_value: false initial_value: '0' - id: sht_seen type: bool restore_value: false initial_value: 'false' - id: last_rh_ms type: uint32_t restore_value: false initial_value: '0' - id: rh_seen type: bool restore_value: false initial_value: 'false' - id: last_co2_ms type: uint32_t restore_value: false initial_value: '0' - id: co2_seen type: bool restore_value: false initial_value: 'false' binary_sensor: - platform: template name: "SHT20 Temperature Fresh" lambda: |- return id(sht_seen) && (uint32_t)(millis() - id(last_sht_ms)) < 35000; - platform: template name: "SHT20 Humidity Fresh" lambda: |- return id(rh_seen) && (uint32_t)(millis() - id(last_rh_ms)) < 35000; - platform: template name: "SCD41 Data Fresh" lambda: |- return id(co2_seen) && (uint32_t)(millis() - id(last_co2_ms)) < 35000; - platform: template name: "CO2 Ventilation Reminder" lambda: |- if (!id(co2_seen) || (uint32_t)(millis() - id(last_co2_ms)) >= 35000) return {}; if (id(co2_value).state >= 1000) return true; if (id(co2_value).state <= 800) return false; return {}; filters: - delayed_on: 60s - delayed_off: 60s

先查供電和共地，再核對端子名稱與訊號方向。I²C 裝置可看掃描位址；PMS5003T 走 UART，不會出現在 I²C 清單。接著確認設定的型號與最後一次更新時間，最後才檢查網頁或後端。資料停住時，不要先把它當成環境一直沒變。

• ESPHome SCD4x
• Seeed Grove SCD41 原廠文件