This integration allows you to monitor your heating and water consumption data from the ista Calista portal within Home Assistant.

• Retrieves historical consumption data for:
  • Heating
  • Hot Water
  • Cold Water
• Provides sensors for the latest readings.
• Stores historical data as Long-Term Statistics (LTS) in Home Assistant.
• Configurable update interval via Options Flow.
• Supports multiple meter types associated with your account.

• An active account on the ista Calista portal.
• Home Assistant installation (Version 2023.1.0 or newer recommended).
• HACS (Home Assistant Community Store) installed.

1. Via HACS (Recommended):
   • Search for "Ista Calista" in the HACS integrations tab.
   • Click "Install".
   • Restart Home Assistant.
2. Manual Installation:
   • Copy the custom_components/ista_calista directory to your Home Assistant custom_components folder.
   • Restart Home Assistant.

1. Go to Settings -> Devices & Services.
2. Click Add Integration.
3. Search for "Ista Calista" and select it.
4. Enter your ista Calista portal email and password.
5. Select the Consumption Start Date: This is the date from which the integration will attempt to import historical data (must be at least 1 month in the past, default is 1 year ago). Note: ista often only provides data for the last 1-2 years.
6. Click Submit.

The integration will connect to your account, retrieve initial data, and create sensors for your meters. This initial sync might take a few minutes depending on the amount of historical data.

You can configure the update interval after installation:

1. Go to Settings -> Devices & Services.
2. Find the Ista Calista integration and click Configure.
3. Adjust the Update Interval (hours) (default is 24 hours, minimum is 1 hour).
4. Click Submit.

The integration creates the following sensors for each detected meter device:

• Heating: Total heating consumption (Unit depends on meter, often kWh or MWh).
• Hot Water: Total hot water consumption (Typically m³).
• Water: Total cold water consumption (Typically m³).
• Last Measured Date: Timestamp of the last reading received from the portal.

These sensors support Long-Term Statistics.

• Authentication Failed: Double-check your email and password. If the issue persists, try logging into the ista Calista portal directly to ensure your credentials are correct.
• Cannot Connect: Verify your Home Assistant instance has internet access. The ista portal might be temporarily unavailable.
• Missing Data/Sensors: Ensure the "Consumption Start Date" is set correctly during setup. Check the Home Assistant logs (home-assistant.log) for errors related to ista_calista or pycalista_ista.

If you encounter issues, please open an issue on GitHub.

Contributions are welcome! Please refer to the contribution guidelines (if any) in the repository.

This integration is not affiliated with, authorized, maintained, sponsored, or endorsed by ista International GmbH or any of its affiliates or subsidiaries. Use at your own risk.