Set hot water override

The Set hot water override action sets the domestic hot water enable option on your OpenTherm Gateway. If the boiler is configured to let the room unit control when to keep a small amount of water preheated, this action can influence that behavior.

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 hot water override 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. From the search box, search for and select OpenTherm Gateway: Set hot water override.
6. Enter the Gateway ID and the Domestic hot water override.
7. Select Save.

This action does not support targets. In the UI, you are not prompted to choose an area, device, entity, or label.

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 opentherm_gw.set_hot_water_ovrd. A basic example looks like this:

action: opentherm_gw.set_hot_water_ovrd
data:
  gateway_id: opentherm_gateway
  dhw_override: "1"

This enables the domestic hot water override in the on state.

Options in YAML

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.

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 hot water setpoint: Sets the domestic hot water setpoint on the gateway.