Set maximum airflow

Use this action to set the maximum airflow for an iZone zone, so the zone never draws more than that much airflow. This is useful to balance your system, for example to stop one room taking all the air from the rest of the house.

Using this action from the user interface

If you prefer building automations and scripts visually, Home Assistant walks you through this action step by step. You pick what to target, tweak a few options, and save. No YAML knowledge required.

To set the maximum airflow from an automation or a script:

1. Go to Settings > Automations & scenes.
2. Open an existing automation or script, or select Create automation > Create new automation.
3. If you’re setting up a new automation, add a trigger in the When section. Scripts don’t need a trigger. They run when something else calls them.
4. In the Then do section, select Add action.
5. Select what you want to control. Under By target (see Targets), select the zone you want to adjust.
6. From the actions shown for that target, select Set maximum airflow.
7. Set the Percent for the maximum airflow.
8. Select Save.

Options in the UI

Using this action in YAML

If you work directly in YAML, or you want to know exactly what Home Assistant does under the hood, this section has the technical reference. It lists the field names you use in YAML, their types, and which ones are required.

In YAML, refer to this action as izone.airflow_max. A basic example looks like this:

action: izone.airflow_max
target:
  entity_id: climate.bed_2
data:
  airflow: 80

This limits the climate.bed_2 zone to at most 80% airflow.

Options in YAML

Targets of the action

This action requires a target. The target is the object of the action. You can point the action at a single entityAn entity represents a sensor, actor, or function in Home Assistant. Entities are used to monitor physical properties or to control other entities. An entity is usually part of a device or a service. [Learn more], a device, an area, a floor, or a label, and Home Assistant will run the action on every matching climate entity behind that target.

• Entity: one specific climate entity, such as climate.living_room.
• Device: every climate entity that belongs to a device.
• Area: every climate entity in a room or area.
• Floor: every climate entity on a floor.
• Label: every climate entity that shares a label.

You can also select different target types in one action. For example, you can add a specific entity and an area as targets in the same action to run the action on both of them at once.

Good to know

• The maximum can’t be lower than the zone’s minimum airflow. Use Set minimum airflow to lower the minimum first if you need a lower maximum.

Try it yourself

Ready to test this? Open Developer tools > Actions, search for this action, fill in the fields, and select Perform action. You see what happens on your actual entitiesAn entity represents a sensor, actor, or function in Home Assistant. Entities are used to monitor physical properties or to control other entities. An entity is usually part of a device or a service. [Learn more] without writing a line of YAML.

More examples

Real scenarios where this action shows up in automations and scripts. Copy any example and adapt it to your setup.

Automation: limit the living room during peak cooling

On hot afternoons, cap the living room airflow so the rest of the house keeps cooling evenly.

• Trigger: Outdoor temperature rises above 30 °C
• Action: iZone: Set maximum airflow on the living room

alias: "Limit living room airflow on hot afternoons"
triggers:
  - trigger: numeric_state
    entity_id: sensor.outdoor_temperature
    above: 30
actions:
  - action: izone.airflow_max
    target:
      entity_id: climate.living_room
    data:
      airflow: 70

Still stuck?

The Home Assistant community is quick to help: join Discord for real-time chat, post on the community forum with the action you’re calling and what you expected to happen, or share on our subreddit /r/homeassistant.

Related actions

These actions work well alongside this one:

• Set minimum airflow: Sets the minimum airflow percentage for an iZone zone.