Thermostat target humidity crossed threshold

The Thermostat target humidity crossed threshold trigger fires after the target humidity (setpoint) of a thermostat 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] crosses a threshold value. Unlike Thermostat target humidity changed, which fires whenever the target changes and lands at a particular value, this trigger fires only at the moment the setpoint crosses from one side of the threshold to the other.

Use this trigger when you want to react to the exact moment a humidity setpoint enters or exits a range, such as when a thermostat is adjusted to a more or less humid target.

Using this trigger from the user interface

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

To use Thermostat target humidity crossed threshold in an automation:

1. Go to Settings > Automations & scenes.
2. Open an existing automation, or select Create automation > Create new automation.
3. In the When section, select Add trigger.
4. Select what you want to monitor. Under By target (see Targets), pick the area your thermostat is in (like your bedroom or living room). You can also select a device, a specific entity, or a label.
5. From the triggers shown for that target, select Thermostat target humidity crossed threshold.
6. Under Threshold type, configure what kind of crossing fires the trigger:
   • Select Above and enter a value (in %) to fire when the setpoint crosses above that value.
   • Select Below and enter a value (in %) to fire when the setpoint crosses below that value.
   • Select In range and enter a lower and upper bound to fire when the setpoint crosses into the range from outside.
   • Select Outside range and enter a lower and upper bound to fire when the setpoint crosses out of the range.
   • For each option, you can enter a fixed percentage or pick a sensor entity or a number helper entity as the threshold.
     • If you don’t have a number helper, you can create one by selecting Create a new number helper.
7. Under Trigger when (see Behavior), pick Each, First, or All to control how the trigger behaves when multiple thermostats are targeted.
8. Under For at least, set how long the thermostat must stay beyond the threshold before the trigger fires. Leave it at zero to fire immediately.
9. Select Save.

Options in the UI

Using this trigger 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, Thermostat target humidity crossed threshold is referred to as climate.target_humidity_crossed_threshold. A basic example looks like this:

trigger: climate.target_humidity_crossed_threshold
target:
  entity_id: climate.bedroom
options:
  threshold:
    type: above
    value:
      number: 55

This fires when the target humidity of climate.bedroom crosses above 55%.

To fire when the setpoint crosses into a comfortable range:

trigger: climate.target_humidity_crossed_threshold
target:
  entity_id: climate.bedroom
options:
  threshold:
    type: between
    value_min:
      number: 40
    value_max:
      number: 60

Options in YAML

YAML sometimes provides additional options for more complex use cases that are not available through the UI.

threshold:
  type: outside
  value_min:
    entity: input_number.comfortable_humidity_min
  value_max:
    number: 60

Targets of the trigger

This trigger requires a target. The target is the object that Home Assistant will watch. You can select 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 as a target, and Home Assistant will watch 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 trigger. For example, you can add a specific entity and an area as targets in the same trigger to monitor both of them at once.

Behavior with multiple targets

When you target more than one entity (or select an area, floor, or label that contains several), the Trigger when option controls how the trigger responds:

• Each (any in YAML, default): the trigger fires every time any one of the targeted entities transitions. For example, if you monitor three motion sensors in the living room and someone walks past sensor 1, the automation fires. When they walk past sensor 2 a moment later, it fires again. Every individual event counts.
• First (first in YAML): the trigger fires only on the first transition in the targeted group, then waits until all targeted entities have reset before it fires again. For example, if you monitor the same three motion sensors, the automation fires when the first one picks up movement (someone entered the room). The other two firing afterward are ignored, so you get one notification per “someone walked in” event instead of three.
• All (last in YAML): the trigger fires only after the last targeted entity in the group has fired, meaning all of them are now in the expected state. For example, if you monitor the lights in the living room, bedroom, and hallway, the automation fires only once all three have turned off. This is useful for scenarios like “start the robot vacuum only after every light on the floor is off,” so you know the room is truly empty.

Good to know

• This trigger monitors the target humidity setpoint (what you want the thermostat to maintain), not the current room humidity (the actual measured humidity). To react to changes in measured room humidity, use Relative humidity crossed threshold instead.
• The threshold type controls the direction of the crossing. Above and Below fire when crossing in one direction through a single value, while In range and Outside range fire when crossing the boundary of a range.
• The trigger fires only at the moment of crossing, not while the setpoint stays beyond the threshold.
• To react to any change that lands at a particular value, use Thermostat target humidity changed instead.
• The trigger only works with climate entities that expose a target humidity attribute. Not all thermostats support humidity control.
• Humidity values are expressed as percentages (0-100%).

Try it yourself

Ready to test this? Go to Settings > Automations & scenes, create a new automation, and add this trigger. Save the automation, then change the state of the targeted entity to watch the trigger fire 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].

More examples

Real scenarios where this trigger fires in automations and scripts. Copy any example and adapt it to your setup.

Automation: activate dehumidifiers when all setpoints cross below comfortable level

When all thermostats in the bedroom area have their target humidity cross below 40%, adjust all standalone dehumidifiers to help maintain a comfortable humidity level. Waiting for all thermostats ensures consistent humidity control across the area.

• Trigger: Thermostat target humidity crossed threshold
  • Target: Bedroom area
  • Threshold type: Below (40%)
  • Trigger when: All
• Action: Set humidifier target humidity

alias: "Activate dehumidifiers when all humidity targets low"
triggers:
  - trigger: climate.target_humidity_crossed_threshold
    target:
      area_id: bedroom
    options:
      threshold:
        type: below
        value:
          number: 40
      behavior: last
actions:
  - action: humidifier.set_humidity
    target:
      entity_id: humidifier.bedroom_dehumidifier
    data:
      humidity: 40

Still stuck?

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

Related triggers

These triggers work well alongside this one:

• Thermostat target humidity changed: Triggers after the humidity setpoint of one or more thermostats changes.

• Thermostat target temperature crossed threshold: Triggers after the temperature setpoint of one or more thermostats crosses a threshold.