Set HVAC mode

Use this action to set the HVAC mode for a NuHeat thermostat.

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 HVAC mode 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 NuHeat thermostat.
  6. From the actions shown for that target, select Set HVAC mode.
  7. Select the HVAC mode.
  8. Select Save.

Options in the UI

HVAC mode

The HVAC mode to set.

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 climate.set_hvac_mode. A basic example looks like this:

ActionActions are used in several places in Home Assistant. As part of a script or automation, actions define what is going to happen once a trigger is activated. In scripts, an action is called *sequence*. [Learn more]
action: climate.set_hvac_mode
target:
  entity_id: climate.bathroom_floor
data:
  hvac_mode: heat

Options in YAML

hvac_mode string Required

The HVAC mode to set.

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

  • NuHeat thermostats do not have an off mode.
  • Setting the temperature to the minimum temperature and changing the mode to heat puts the thermostat in Permanent Hold and stops heating unless freeze protection is needed.

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.

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.

Tip

AI assistants like ChatGPT or Claude can also explain actions or suggest the right one when you describe what you want in plain language.

Related actions

These actions work well alongside this one: