🌡️ Automatic Room Heating Based on Window State

This guide explains how to set up a smart heating automation in Home Assistant that reacts to your window sensors to maximize comfort and save energy.

• Window Opened: The heating in the corresponding room will automatically turn off.
• Window Closed: The heating will restore the last manually set temperature for that room.

⚙️ Requirements

• A working Home Assistant installation
• Climate integrations (thermostats) for each room
• Binary sensors for windows or doors
• Input Number helpers to store the last set temperature

🔧 Setting Up Input Number Helpers

Input Numbers are used to remember the last desired temperature for each room. Example configuration for the living room:

Copywohnzimmer_last_temp:
  name: Living Room Last Temperature
  min: 5
  max: 30
  step: 0.1
  unit_of_measurement: "°C"
  initial: 23.5

💾 Automation Example (Per Room)

This automation triggers whenever a window sensor changes state. When the window opens, it stores the current temperature and turns off the heater. When the window closes, it restores the previous temperature.

Copyalias: Living Room Window Heating Control
trigger:
  - platform: state
    entity_id: binary_sensor.living_room_windows
condition: []
action:
  - choose:
      - conditions:
          - condition: state
            entity_id: binary_sensor.living_room_windows
            state: "on"
        sequence:
          - service: input_number.set_value
            target:
              entity_id: input_number.wohnzimmer_last_temp
            data:
              value: "{{ state_attr('climate.living_room', 'temperature') }}"
          - service: climate.turn_off
            target:
              entity_id: climate.living_room
      - conditions:
          - condition: state
            entity_id: binary_sensor.living_room_windows
            state: "off"
        sequence:
          - service: climate.set_temperature
            target:
              entity_id: climate.living_room
            data:
              temperature: "{{ states('input_number.wohnzimmer_last_temp') | float }}"
mode: single

📄 Notes and Best Practices

• Each room should have its own automation with its respective thermostat and window sensors.
• Input Numbers store the last manually set temperature, ensuring the system always restores your preferred comfort level.
• This approach works with multiple windows per room and automatically reacts to any open or closed state.
• You can expand this logic to include doors, guest rooms, or any other zones in your house.
• Optional: Combine with Home Assistant presence detection or HVAC schedules for even smarter energy savings.

⚡ Summary

This automation setup ensures:

• Energy savings by turning off heating when windows are open.
• Comfort restoration by automatically setting the last preferred temperature when windows close.
• Scalability: Add as many rooms as you need with separate automations and temperature memory.