Water heater target temperature changed

The Water heater target temperature changed trigger fires when the target temperature setting of a water heater 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] changes. The target temperature is the setpoint you want the water heater to maintain, not the current measured water temperature. Use this trigger when you want to react to any meaningful setpoint change, like sending an alert when someone raises the target temperature higher than usual.

Use the threshold type to decide which changes matter. You can fire on any change, only when the new setpoint is above or below a value, or only when it lands inside or outside a range.

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 Water heater target temperature changed 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 water heater is in, or select a device, a specific entity, a floor, or a label.
5. From the triggers shown for that target, select Water heater target temperature changed.
6. Under Threshold type, choose which kind of setpoint change should fire the trigger:
   • Select Any change to fire on any setpoint change.
   • Select Above or Below to fire only when the new setpoint lands above or below a value.
   • Select In range or Outside range to fire only when the new setpoint lands inside or outside a range.
   • You can use a fixed number or select a temperature sensor, a temperature number entity, or a number helper as the threshold.
   • If you need a helper, create the helperA helper is a virtual entity you create inside Home Assistant. It is not backed by a physical device. Helpers store values, track state, or do calculations that your automations and dashboards need. [Learn more] separately before using it here.
7. Under Unit, select the temperature unit to use for the comparison when you enter a number.
8. 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, Water heater target temperature changed is referred to as water_heater.target_temperature_changed. A basic example looks like this:

trigger: water_heater.target_temperature_changed
target:
  entity_id: water_heater.utility_room
options:
  threshold:
    type: above
    value:
      number: 55
      unit_of_measurement: "°C"

This fires when the target temperature of water_heater.utility_room changes to a value above 55°C.

To fire when the setpoint lands outside a preferred range:

trigger: water_heater.target_temperature_changed
target:
  entity_id: water_heater.utility_room
options:
  threshold:
    type: outside
    value_min:
      entity: input_number.water_heater_min_target
    value_max:
      entity: input_number.water_heater_max_target

Options in YAML

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

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 water_heater entity behind that target.

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

Good to know

• This trigger watches the target temperature setpoint, not the current measured water temperature.
• To react only when the setpoint crosses a threshold boundary, use Water heater target temperature crossed threshold.
• When you use an entity as the threshold, Home Assistant uses that entity’s current value when the setpoint changes.
• The threshold entities must provide temperature values. Supported threshold sources are temperature sensors, temperature number entities, and input_number helpers.

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: notify when the target temperature is raised above a safe routine

When someone raises the water heater target temperature above your usual daily setting, send a notification so you can double-check the change.

• Trigger: Water heater target temperature changed
  • Target: Utility room water heater
  • Threshold type: Above (55°C)
• Action: Send a notification message
  • Target: My Device (notify.my_device)

alias: "Notify when the water heater target temperature is raised"
triggers:
  - trigger: water_heater.target_temperature_changed
    target:
      entity_id: water_heater.utility_room
    options:
      threshold:
        type: above
        value:
          number: 55
          unit_of_measurement: "°C"
actions:
  - action: notify.send_message
    target:
      entity_id: notify.my_device
    data:
      message: "The water heater target temperature is now above 55°C."

Automation: switch to Eco mode when the setpoint returns to the normal range

When the target temperature is changed back into your normal range, switch the water heater back to an energy-saving mode.

• Trigger: Water heater target temperature changed
  • Target: Utility room water heater
  • Threshold type: In range (50-52°C)
• Action: Set water heater operation mode

alias: "Return water heater to Eco mode"
triggers:
  - trigger: water_heater.target_temperature_changed
    target:
      entity_id: water_heater.utility_room
    options:
      threshold:
        type: between
        value_min:
          number: 50
          unit_of_measurement: "°C"
        value_max:
          number: 52
          unit_of_measurement: "°C"
actions:
  - action: water_heater.set_operation_mode
    target:
      entity_id: water_heater.utility_room
    data:
      operation_mode: eco

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:

• Water heater target temperature crossed threshold: Triggers after the temperature setpoint of one or more water heaters crosses a threshold.

• Water heater operation mode changed: Triggers after the operation mode of one or more water heaters changes to a specific mode.