Bath fan automation baed on humidity

fan_automation.yaml

blueprint:
  name: Humidity-Controlled Fan with Manual Override
  description: >
    Automate a bathroom fan to turn on/off based on humidity levels with manual override and configurable timer. Includes automatic helper creation and a dashboard card.
  domain: automation
  input:
    fan_switch:
      name: Fan Switch
      description: The fan switch entity.
      selector:
        entity:
          domain: switch
    bathroom_humidity:
      name: Bathroom Humidity Sensor
      description: The humidity sensor in the bathroom.
      selector:
        entity:
          domain: sensor
          device_class: humidity
    indoor_humidity:
      name: Indoor Humidity Sensor
      description: The main house humidity sensor to compare against.
      selector:
        entity:
          domain: sensor
          device_class: humidity
    humidity_on_threshold:
      name: Humidity On Threshold
      description: Humidity percentage that triggers the fan ON.
      default: 65
      selector:
        number:
          min: 50
          max: 90
          unit_of_measurement: "%"
          step: 1
    humidity_off_threshold:
      name: Humidity Off Threshold
      description: Humidity percentage that triggers the fan OFF.
      default: 62
      selector:
        number:
          min: 40
          max: 80
          unit_of_measurement: "%"
          step: 1
    humidity_delta:
      name: Humidity Delta
      description: Difference between bathroom and house humidity to consider for triggering.
      default: 5
      selector:
        number:
          min: 1
          max: 20
          unit_of_measurement: "%"
          step: 1
    manual_override_duration:
      name: Manual Override Duration (minutes)
      description: Time to keep the fan running when turned on manually.
      default: 20
      selector:
        number:
          min: 5
          max: 60
          unit_of_measurement: minutes
          step: 1

automation:
  - alias: Setup Bath Fan Helpers
    trigger:
      - platform: homeassistant
        event: start
    action:
      - service: input_boolean.create
        data:
          name: Bath Fan Manual Override
          entity_id: input_boolean.bath_fan_manual_override
      - service: input_number.create
        data:
          name: Bath Fan Override Duration
          entity_id: input_number.bath_fan_override_duration
          min: 5
          max: 60
          step: 1
          unit_of_measurement: minutes
          mode: slider

trigger:
  - platform: numeric_state
    entity_id: !input bathroom_humidity
    above: !input humidity_on_threshold
    id: humidity_high
  - platform: numeric_state
    entity_id: !input bathroom_humidity
    below: !input humidity_off_threshold
    id: humidity_low
  - platform: state
    entity_id: !input fan_switch
    to: "on"
    id: manual_on

variables:
  fan_switch: !input fan_switch
  bathroom_humidity: !input bathroom_humidity
  indoor_humidity: !input indoor_humidity
  humidity_on_threshold: !input humidity_on_threshold 
  humidity_off_threshold: !input humidity_off_threshold 
  humidity_delta: !input humidity_delta 
  manual_override_duration: !input manual_override_duration 
  override_flag: "input_boolean.bath_fan_manual_override"

action:
  - choose:
      - conditions:
          - condition: trigger
            id: humidity_high
          - condition: template
            value_template: >
              {{ states(bathroom_humidity)|float - states(indoor_humidity)|float > humidity_delta }}
          - condition: state
            entity_id: "{{ override_flag }}"
            state: "off"
        sequence:
          - service: switch.turn_on
            target:
              entity_id: "{{ fan_switch }}"
      - conditions:
          - condition: trigger
            id: manual_on
          - condition: state
            entity_id: "{{ override_flag }}"
            state: "off"
        sequence:
          - service: input_boolean.turn_on
            target:
              entity_id: "{{ override_flag }}"
          - delay:
              minutes: "{{ manual_override_duration }}"
          - service: input_boolean.turn_off
            target:
              entity_id: "{{ override_flag }}"
          - choose:
              - conditions:
                  - condition: template
                    value_template: >
                      {{ states(bathroom_humidity)|float > humidity_on_threshold and
                         (states(bathroom_humidity)|float - states(indoor_humidity)|float > humidity_delta) }}
                sequence:
                  - service: switch.turn_on
                    target:
                      entity_id: "{{ fan_switch }}"
      - conditions:
          - condition: trigger
            id: humidity_low
          - condition: state
            entity_id: "{{ override_flag }}"
            state: "off"
        sequence:
          - service: switch.turn_off
            target:
              entity_id: "{{ fan_switch }}"

mode: restart

📱 Dashboard Card YAML

Add this to your Lovelace dashboard

views:
  - title: Bathroom Fan Control
    cards:
      - type: entities
        title: Bath Fan Control
        entities:
          - entity: !input fan_switch
            name: Fan Switch
          - entity: input_boolean.bath_fan_manual_override
            name: Manual Override Active
          - entity: input_number.bath_fan_override_duration
            name: Override Duration (minutes)