Komfovent integration for Home Assistant

A Home Assistant integration for Komfovent C6, C6M and C8 ventilation units through Modbus TCP.

Features

The integration provides comprehensive control and monitoring of your Komfovent ventilation unit:

Climate Control

• Temperature control with multiple modes (supply, extract, room, balance)
• Setpoint adjustment for all operation modes
• Real-time HVAC action monitoring (heating, cooling, fan, idle, off)
• ECO mode settings with min/max temperature limits
• Free heating/cooling control
• Heater and cooler blocking options

Operation Modes

• Away - Low-intensity ventilation
• Normal - Standard ventilation
• Intensive - Increased ventilation
• Boost - Maximum ventilation
• Kitchen - Temporary increased ventilation for cooking
• Fireplace - Special mode for fireplace operation
• Override - Override current schedule
• Holiday - Scheduled absence periods
• Air Quality - Automatic control based on air quality

Air Quality Control

• CO2 monitoring and control
• VOC (Volatile Organic Compounds) monitoring
• Humidity monitoring and control
• Adjustable setpoints and intensity ranges
• Impurity control settings

Monitoring

• Supply and extract air temperatures
• Outdoor and exhaust air temperatures
• Fan speeds and flow rates
• Heat exchanger efficiency
• Filter status
• Power consumption
• Energy recovery
• Specific power input (SPI)
• Active alarms monitoring
• Comprehensive alarm status (fault/warning indicators)

Advanced Features

• Electric heater control for each mode
• Timer-based operation for kitchen/fireplace/override modes
• Scheduler operation with multiple modes
• System time synchronization
• Clean filters calibration
• Firmware version monitoring
• Detailed diagnostics
• Clear active alarms remotely

All features are exposed as Home Assistant entities, allowing for easy integration into automations and the user interface.

Services

The integration provides several services that can be called from Home Assistant actions:

Clean Filters Calibration

Calibrates the clean filters on the Komfovent unit after filter replacement:

# Example service call
action: komfovent.clean_filters_calibration
target:
  device_id: YOUR_DEVICE_ID

Set Operation Mode

Sets the operation mode of the Komfovent unit:

# Example service call
action: komfovent.set_operation_mode
target:
  device_id: YOUR_DEVICE_ID
data:
  mode: kitchen
  minutes: 60

Available modes:

• off: Turn off the unit
• air_quality: Enable automatic air quality control
• away: Low-intensity ventilation for when you're away
• normal: Standard ventilation mode
• intensive: Increased ventilation
• boost: Maximum ventilation
• kitchen: Temporary increased ventilation for cooking
• fireplace: Special mode for fireplace operation
• override: Override current schedule

The minutes parameter (1-300) is only used for kitchen, fireplace, and override modes.

# Example action in a button card
show_name: true
show_icon: true
type: button
entity: select.komfovent_current_mode
name: Kitchen
icon: mdi:stove
show_state: false
tap_action:
  action: perform-action
  perform_action: komfovent.set_operation_mode
  target:
    device_id: YOUR_DEVICE_ID
  data:
    mode: kitchen
    minutes: 5

Clear Active Alarms

Clears active fault and warning alarms on the Komfovent unit:

# Example service call
action: komfovent.clear_active_alarms
target:
  device_id: YOUR_DEVICE_ID

Set System Time

Sets the system time on the Komfovent unit to match the local time:

# Example service call
action: komfovent.set_system_time
target:
  device_id: YOUR_DEVICE_ID

Device support

Currently only the Komfovent C6, C6M and C8 devices are supported, however due to the large variety of configurations, not every combination has been tested yet.

If you have connectivity issues, please confirm that you have the latest firmware on your Komfovent device. Depending on the controller type, please see the manufacturer's update instructions.

• C6/C6M firmware update instructions
• C8 firmware update instructions

If you have issues seeing the data correctly, then please open a new ticket with:

• the model of your device, controller type and firmware version
• screenshots of the data in the Komfovent app or web interface
• diagnostic data from the Komfovent device (see below)

Installation

1. Add this repository to HACS or copy the custom_components/komfovent folder to your Home Assistant configuration directory.
2. Restart Home Assistant.
3. Add the integration through the Home Assistant UI.
4. Configure the integration with the IP address of your Komfovent device.

Configuration

The integration can be configured through the Home Assistant UI.

Initial Setup

During initial setup, you'll configure:

• name: The name of your Komfovent device
• Host: The IP address of your Komfovent device
• Port: The Modbus TCP port (default: 502)

After setup, the device info will include a direct link to the device's web interface for easy access.

Advanced Options

After installation, you can configure advanced options through the integration's options menu:

• Update Interval: How often to fetch data from the device (10-300 seconds, default: 30 seconds)
• EMA Time Constant: Temperature smoothing filter time constant (0-900 seconds, default: 300 seconds)
  • Set to 0 to disable temperature smoothing
  • Higher values provide more smoothing but slower response to temperature changes
• Step Thresholds: Minimum change thresholds for various sensor types (flow, temperature, humidity, CO2, VOC, timer)
  • Helps reduce noise and unnecessary updates

ModBus tools

The scripts/modbus_dump.py tool can be used to dump the ModBus data from the Komfovent device. Usage:

python3 scripts/modbus_dump.py --host <device_ip> [--port 502] [--output registers.json]

This will scan all known register ranges and save the results to a JSON file. The tool supports these arguments:

• --host: Required. IP address of your Komfovent device
• --port: Optional. ModBus TCP port (default: 502)
• --output: Optional. Output JSON file path (default: registers.json)

The scripts/modbus_server.py tool can be used to simulate a Komfovent ModBus server for testing purposes. Usage:

python3 scripts/modbus_server.py [--host 0.0.0.0] [--port 502] [--input registers.json]

This will start a ModBus TCP server that simulates a Komfovent device using register values from a JSON file. The tool supports these arguments:

• --host: Optional. Network interface to listen on (default: 0.0.0.0)
• --port: Optional. ModBus TCP port to listen on (default: 502)
• --input: Optional. Input JSON file with register values (default: registers.json)

You can use this tool for development and testing without needing a physical device. First dump the registers from a real device, then use that JSON file to run the simulator.

Repository Overview

This repository contains multiple files, here is an overview:

File	Purpose	Documentation
.devcontainer.json	Used for development/testing with Visual Studio Code.	Documentation
.github/ISSUE_TEMPLATE/*.yml	Templates for the issue tracker	Documentation
custom_components/komfovent/*	Integration files, this is where everything happens.	Documentation
CONTRIBUTING.md	Guidelines on how to contribute.	Documentation
LICENSE	The license file for the project.	Documentation
README.md	The file you are reading now, should contain info about the integration, installation, and configuration instructions.	Documentation
pyproject.toml	Python project metadata and dependencies used for development/lint/testing this integration.	Documentation
uv.lock	Lock file for reproducible dependency installations using uv.	Documentation