aiohomematic 2026.1.20

Homematic interface for Home Assistant running on Python 3.

aiohomematic

A modern, async Python library for controlling and monitoring Homematic and HomematicIP devices. Powers the Home Assistant integration "Homematic(IP) Local". Some third-party devices/gateways (e.g., Bosch, Intertechno) may be supported as well.

This project is the modern successor to pyhomematic, focusing on automatic entity creation, fewer manual device definitions, and faster startups.

Key Features

• Automatic entity discovery from device/channel parameters
• Extensible via custom entity classes for complex devices (thermostats, lights, covers, locks, sirens)
• Fast startups through caching of paramsets
• Robust operation with automatic reconnection after CCU restarts
• Fully typed with strict mypy compliance
• Async/await based on asyncio

How It Works

Unlike pyhomematic, which required manual device mappings, aiohomematic automatically creates entities for each relevant parameter on every device channel (unless blacklisted). To achieve this it:

• Fetches and caches device paramsets (VALUES) for fast successive startups
• Provides hooks for custom entity classes where complex behavior is needed
• Includes helpers for robust operation, such as automatic reconnection after CCU restarts

Relationship to Homematic(IP) Local

This project follows a two-layer architecture that separates concerns between the library and the Home Assistant integration:

┌─────────────────────────────────────────────────────────┐
│                    Home Assistant                        │
│                                                          │
│  ┌────────────────────────────────────────────────────┐ │
│  │           Homematic(IP) Local Integration          │ │
│  │                                                    │ │
│  │  • Home Assistant entities (climate, light, etc.)  │ │
│  │  • UI configuration flows                          │ │
│  │  • Services and automations                        │ │
│  │  • Device/entity registry integration              │ │
│  └────────────────────────┬───────────────────────────┘ │
└───────────────────────────┼─────────────────────────────┘
                            │
                            │ uses
                            ▼
┌───────────────────────────────────────────────────────────┐
│                      aiohomematic                         │
│                                                           │
│  • Protocol implementation (XML-RPC, JSON-RPC)            │
│  • Device model and data point abstraction                │
│  • Connection management and reconnection                 │
│  • Event handling and callbacks                           │
│  • Caching for fast startups                              │
└───────────────────────────────────────────────────────────┘
                            │
                            │ communicates with
                            ▼
┌───────────────────────────────────────────────────────────┐
│              CCU3 / OpenCCU / Homegear                    │
└───────────────────────────────────────────────────────────┘

Why Two Projects?

Aspect	aiohomematic	Homematic(IP) Local
Purpose	Python library for Homematic protocol	Home Assistant integration
Scope	Protocol, devices, data points	HA entities, UI, services
Dependencies	Standalone (aiohttp, orjson)	Requires Home Assistant
Reusability	Any Python project	Home Assistant only
Repository	aiohomematic	homematicip_local

Benefits of this separation:

• Reusability: aiohomematic can be used in any Python project, not just Home Assistant
• Testability: The library can be tested independently without Home Assistant
• Maintainability: Protocol changes don't affect HA-specific code and vice versa
• Clear boundaries: Each project has a focused responsibility

How They Work Together

1. Homematic(IP) Local creates a CentralUnit via aiohomematic's API
2. aiohomematic connects to the CCU/Homegear and discovers devices
3. aiohomematic creates Device, Channel, and DataPoint objects
4. Homematic(IP) Local wraps these in Home Assistant entities
5. aiohomematic receives events from the CCU and notifies subscribers
6. Homematic(IP) Local translates events into Home Assistant state updates

For Developers

If you want to:

• Use Homematic devices in Home Assistant → Install Homematic(IP) Local
• Build a custom Python application → Use aiohomematic directly
• Contribute to device support → Most changes go into aiohomematic
• Fix HA-specific issues → Changes go into Homematic(IP) Local

Requirements

Python

• Python 3.13 or higher

CCU Firmware

Due to a bug in earlier CCU2/CCU3 firmware, aiohomematic requires at least the following versions when used with HomematicIP devices:

Platform	Minimum Version
CCU2	2.53.27
CCU3	3.53.26

See details: OpenCCU Issue #843

Installation

For Home Assistant Users

Use the Home Assistant custom integration "Homematic(IP) Local", which is powered by aiohomematic:

1. Prerequisites

   • Latest version of Home Assistant
   • A CCU3, OpenCCU, or Homegear instance reachable from Home Assistant
   • For HomematicIP devices, ensure CCU firmware meets the minimum versions listed above

2. Install the integration

   • Add the custom repository: https://github.com/sukramj/homematicip_local
   • Follow the installation guide

3. Configure via Home Assistant UI

   • Settings → Devices & Services → Add Integration → "Homematic(IP) Local"
   • Enter CCU/Homegear host (IP or hostname)
   • Enable TLS if using HTTPS (skip verification for self-signed certificates)
   • Enter credentials
   • Choose interfaces: HM (2001), HmIP (2010), Virtual (9292)

4. Network callbacks

   • Ensure Home Assistant is reachable from the CCU (no NAT/firewall blocking)

New to Homematic? See the Glossary for definitions of terms like Backend, Interface, Device, Channel.

For Developers

pip install aiohomematic

Or install from source:

git clone https://github.com/sukramj/aiohomematic.git
cd aiohomematic
pip install -r requirements.txt

Quick Start

from aiohomematic.central import CentralConfig
from aiohomematic.client import InterfaceConfig, Interface

config = CentralConfig(
    central_id="ccu-main",
    host="ccu.local",
    username="admin",
    password="secret",
    default_callback_port=43439,
    interface_configs={
        InterfaceConfig(interface=Interface.HMIP, port=2010, enabled=True)
    },
)

central = config.create_central()
await central.start()

# Access devices
for device in central.devices:
    print(f"{device.name}: {device.device_address}")

await central.stop()

Public API

The public API is explicitly defined via __all__ in each module:

Module	Contents
aiohomematic.central	CentralUnit, CentralConfig and related schemas
aiohomematic.client	Client, InterfaceConfig, Interface
aiohomematic.model	Device/channel/data point abstractions
aiohomematic.exceptions	Library exception types
aiohomematic.const	Constants and enums

Import from specific submodules for stable imports:

from aiohomematic.central import CentralConfig, CentralUnit
from aiohomematic.client import InterfaceConfig, Interface
from aiohomematic.exceptions import ClientException

Documentation

For Users

• Changelog - Release history and latest changes
• Calculated data points - Derived metrics
• Naming conventions - How names are created
• Input select helper - Using input select helpers
• Troubleshooting - Common issues and debugging
• Unignore mechanism - Unignoring default-ignored devices

For Developers

• Architecture overview - Library architecture
• Data flow - How data flows through the library
• Extension points - Adding custom device profiles
• Home Assistant lifecycle - Integration internals
• Sequence diagrams - Interaction flows
• RSSI fix - RSSI value handling

Contributing

Contributions are welcome! Please read our Contributing Guide for details on:

• Development environment setup
• Code standards and type annotations
• Pull request process
• Testing guidelines

See CLAUDE.md for comprehensive development guidelines.

Related Projects

• Homematic(IP) Local - Home Assistant integration

License

This project is licensed under the MIT License - see the LICENSE file for details.

Support

If you find this project useful, consider sponsoring the development.