ESPHome config for Air Quality Sensor (ENS160+AHT20)

air-quality.yaml

esphome:
  name: air-quality
  comment: "${device_description}"
  friendly_name: Air Quality

substitutions:
  device_description: "Air Quality Sensor (ENS160+AHT20)"
  device_name: "air-quality"
  ens160_update_interval: "100s"
  aht20_update_interval: "60s"
  # when using a combo borad with ENS160+AHT20 there is an issue...
  # the heater of the ENS160 significantly warms up the AHT21 as there is an increase of about 6 °C when the ENS160 is producing data
  # so, there is a workaround:
  #temperature_offset: "-6.0" #"-6.5"
  #humidity_offset: "15" #"12.5"

esp8266:
  board: d1_mini

# Enable logging
logger:

# Enable Home Assistant API
api:
  encryption:
    key: !secret api_encryption_key
  reboot_timeout: 0s

ota:
  - platform: esphome
    password: !secret ota_password

wifi:
  ssid: !secret wifi_ssid
  password: !secret wifi_password

  # Enable fallback hotspot (captive portal) in case wifi connection fails
  ap:
    ssid: "Air-Quality Fallback Hotspot"
    password: !secret ap_password

captive_portal:

# for reset_reason sensor
debug:
  update_interval: 60s

# Restart button
button:
  - platform: restart
    name: Restart

i2c:
  sda: D2
  scl: D1
  scan: true
  id: bus_a

number:

  # Temperature Offset
  - platform: template
    id: temperature_offset
    name: Temperature Offset
    icon: mdi:plus-minus-variant
    optimistic: true
    mode: slider
    step: 1
    entity_category: config
    min_value: -20
    max_value: 20
    initial_value: -6
    restore_value: yes

  # Humidity Offset
  - platform: template
    id: humidity_offset
    name: Humidity Offset
    icon: mdi:plus-minus-variant
    optimistic: true
    mode: slider
    step: 1
    entity_category: config
    min_value: -50
    max_value: 50
    initial_value: 15
    restore_value: yes

text_sensor:

  - platform: debug
    reset_reason:
      name: Reset Reason

  # Uptime Human Readable
  - platform: template
    name: Uptime HR
    id: uptime_human
    icon: mdi:clock-start
    entity_category: "diagnostic"
  
  # Air Quality Text
  - platform: template
    name: "Air Quality Rating"
    id: ens160_air_quality_rating
    icon: mdi:chart-areaspline

  # eCO2 Level Text
  - platform: template
    name: "eCO2 Rating"
    id: ens160_eco2_rating
    icon: mdi:chart-areaspline

  # TVOC Level Text
  - platform: template
    name: "TVOC Rating"
    id: ens160_tvoc_rating
    icon: mdi:chart-areaspline

# binary sensor indicating active warning
binary_sensor:
  - platform: template
    name: "Air Quality Warning"
    id: air_quality_warning
    icon: mdi:bell-alert

  - platform: template
    name: "CO2 Warning"
    id: co2_warning
    icon: mdi:bell-alert

  - platform: template
    name: "TVOC Warning"
    id: tvoc_warning
    icon: mdi:bell-alert

sensor:

  - platform: ens160_i2c
    eco2:
      name: "ENS160 eCO2"
      id: ens160_eco2
      on_raw_value:
       then:
        - text_sensor.template.publish:
            id: ens160_eco2_rating
            state: !lambda |-
              float co2 = (float)x;
              id(co2_warning).publish_state(co2>1000);
              if (co2<700) return {"Excellent"};
              if ((co2>=700)&&(co2<900)) return {"Good"};
              if ((co2>=900)&&(co2<1100)) return {"Fair"};
              if ((co2>=1100)&&(co2<1600)) return {"Mediocre (Contaminated indoor air. Ventilation recommended)"};
              if ((co2>=1600)&&(co2<2200)) return {"Bad (Heavily contaminated indoor air. Ventilation required)"};
              if (co2>=2200) return {"Deadly dangerous!"};
              return {"NA"};
    tvoc:
      name: "ENS160 Total Volatile Organic Compounds"
      id: ens160_tvoc
      on_raw_value:
       then:
        - text_sensor.template.publish:
            id: ens160_tvoc_rating
            state: !lambda |-
              float tvoc = (float)x;
              id(tvoc_warning).publish_state(tvoc>700);
              if (tvoc<65) return {"Excellent"};
              if ((tvoc>=65)&&(tvoc<220)) return {"Good. Ventilation recommended"};
              if ((tvoc>=220)&&(tvoc<660)) return {"Moderate. Ventilation recommended"};
              if ((tvoc>=660)&&(tvoc<2200)) return {"Poor. Ventilation required"};
              if ((tvoc>=2200)&&(tvoc<5500)) return {"Unhealthy. Intensified entilation required"};
              if (tvoc>=5500) return {"Deadly dangerous!"};
              return {"NA"};
    aqi:
      id: ens160_air_quality_index
      name: "ENS160 Air Quality Index"
      on_raw_value:
       then:
        - text_sensor.template.publish:
            id: ens160_air_quality_rating
            state: !lambda |-
             int q = (int)x;
             id(air_quality_warning).publish_state(q>3);
             switch ( q ) {
              case 1: return {"Excellent"};
              case 2: return {"Good"};
              case 3: return {"Moderate"};
              case 4: return {"Poor"};
              case 5: return {"Unhealthy"};
              default: return {"NA"};
             }      
    update_interval: ${ens160_update_interval}
    address: 0x53
    compensation:
      temperature: aht20_temperature
      humidity: aht20_humidity

  - platform: aht10
    variant: AHT20
    temperature:
      name: "AHT20 Temperature"
      id: aht20_temperature
      filters:
        #- offset: ${temperature_offset}
        - lambda: |-
            return x+id(temperature_offset).state;
    humidity:
      name: "AHT20 Humidity"
      id: aht20_humidity
      filters: 
        #- offset: ${humidity_offset}
        - lambda: |-
            return x+id(humidity_offset).state;
    update_interval: ${aht20_update_interval}
    address: 0x38    

  # Uptime sensor.
  - platform: uptime
    name: Uptime
    entity_category: "diagnostic"
    id: esp_uptime
    update_interval: 60s
    on_raw_value:
      then:
        - text_sensor.template.publish:
            id: uptime_human
            state: !lambda |-
              int seconds = round(id(esp_uptime).raw_state);
              int days = seconds / (24 * 3600);
              seconds = seconds % (24 * 3600);
              int hours = seconds / 3600;
              seconds = seconds % 3600;
              int minutes = seconds /  60;
              seconds = seconds % 60;
              return (
                (days ? to_string(days) + "d " : "") +
                (hours ? to_string(hours) + "h " : "") +
                (minutes ? to_string(minutes) + "m " : "") +
                (to_string(seconds) + "s")
              ).c_str();   

  # WiFi Signal sensor.
  - platform: wifi_signal
    name: "WiFi Signal dB"
    id: wifi_signal_db
    entity_category: "diagnostic"
    update_interval: 60s
  - platform: copy # Reports the WiFi signal strength in %
    source_id: wifi_signal_db
    name: "WiFi Signal Percent"
    filters:
        - lambda: return min(max(2 * (x + 100.0), 0.0), 100.0);
    unit_of_measurement: "%"
    entity_category: "diagnostic"
    device_class: ""

# Enable Web server.
web_server:
  port: 80