Asynchronous Python client for the Fumis WiRCU API.

This package allows you to control and monitor Fumis WiRCU pellet stove devices programmatically. It is mainly created to allow third-party programs to automate the behavior of a Fumis WiRCU device.

An excellent example of this might be Home Assistant, which allows you to write automations, to turn on your pellet stove and set a target temperature.

Known compatible stove brands:

• Austroflamm (Clou Duo, MO DUO, Polly 2.0)
• Heta (Green 200)
• HAAS+SOHN
• Eco Spar (Auriga, Solara, Tukana, Karina, Nova)
• Prity

pip install fumis

To install with the optional CLI:

pip install "fumis[cli]"

The optional CLI lets you control your stove directly from the terminal. The --mac and --password options can also be set via the FUMIS_MAC and FUMIS_PASSWORD environment variables.

# Set credentials once via environment variables
export FUMIS_MAC=AABBCCDDEEFF
export FUMIS_PASSWORD=1234

# Launch the live TUI dashboard
fumis

# Show device information
fumis info

# Turn the stove on/off
fumis on
fumis off

# Set target temperature
fumis temperature 23.5

# Set power level (1-5)
fumis power 3

# Enable/disable eco mode
fumis eco true

# Show weekly timer schedule / enable / disable
fumis timer
fumis timer true

# Sync the stove's clock to your system time
fumis sync-clock

# Show service diagnostics (sensors, IO, temperature channels)
fumis diagnostics

# Dump raw API response as JSON
fumis dump

# Emit machine-readable JSON
fumis info --json

The default command (no subcommand) launches a live TUI dashboard with real-time temperature graphs, status display, and keyboard controls for on/off, temperature, and power level.

The client is an async context manager; every API call is a coroutine:

import asyncio

from fumis import Fumis, StoveStatus


async def main() -> None:
    """Show example on controlling your Fumis WiRCU device."""
    async with Fumis(mac="AABBCCDDEEFF", password="1234") as fumis:
        info = await fumis.update_info()

        # Stove identity
        print(info.controller.manufacturer)  # "Austroflamm"
        print(info.controller.model_name)    # "Clou Duo"

        # Status
        print(info.controller.stove_status)  # StoveStatus.OFF
        print(info.controller.on)            # False

        # Temperatures
        main_temp = info.controller.main_temperature
        if main_temp:
            print(f"Room: {main_temp.actual}° → {main_temp.setpoint}°")

        # Combustion chamber
        print(info.controller.combustion_chamber_temperature)

        # Power
        print(f"{info.controller.power.kw} kW (level {info.controller.power.set_power})")

        # Door sensor
        print(f"Door open: {info.controller.door_open}")

        # Fuel level
        fuel = info.controller.fuel()
        if fuel:
            print(f"Fuel: {fuel.quantity_percentage}%")

        # Weekly timer schedule
        schedule = info.controller.schedule
        print(f"Timer: {'on' if info.controller.timer_enable else 'off'}")
        for prog in schedule.programs:
            if prog.active:
                print(f"  {prog}")  # "21:00-22:10"
        print(f"Active days: {schedule.active_days}")

        # Control the stove
        await fumis.turn_on()
        await fumis.set_target_temperature(23.0)
        await fumis.set_power(3)
        await fumis.set_eco_mode(enabled=True)
        await fumis.set_timer(enabled=True)
        await fumis.set_fan_speed(3)
        await fumis.set_clock()
        await fumis.turn_off()


if __name__ == "__main__":
    asyncio.run(main())

For diagnostics, debugging, or fixture capture (useful for Home Assistant diagnostic downloads):

async with Fumis(mac="AABBCCDDEEFF", password="1234") as fumis:
    # Get the raw, unprocessed JSON dict from the API
    raw = await fumis.raw_status()
    print(json.dumps(raw, indent=2))

All diagnostic variables and parameters from the Fumis controller are accessible via the structured model:

info = await fumis.update_info()
c = info.controller

# Convenience properties (return None if not available)
c.exhaust_temperature     # Exhaust gas temp (var[11])
c.fan1_speed              # Fan 1 speed (var[4])
c.fan2_speed              # Fan 2 speed (var[12])
c.f02                     # F02 sensor input (var[34])
c.pressure                # Pressure sensor (var[35])
c.door_open               # Door sensor (var[33]) - True/False/None
c.stove_model             # Stove model ID (var[96])
c.parameter_version       # Parameter version (var[97])
c.backwater_temperature   # Backwater temp for hydronic stoves (var[22])

# Raw diagnostic access (escape hatch)
c.diagnostic.variable(42)   # Any variable by ID → int | None
c.diagnostic.parameter(14)  # Any parameter by ID → int | None

# All temperature channels
for temp in c.temperatures:
    print(f"  Channel {temp.id}: {temp.actual}° (on screen: {temp.on_main_screen})")

# Iterate fans, fuels, etc.
for fan in c.fans:
    print(f"  Fan {fan.id}: speed {fan.speed}")

The exception hierarchy allows catching at any granularity:

from fumis import (
    Fumis,
    FumisAuthenticationError,
    FumisConnectionError,
    FumisConnectionTimeoutError,
    FumisError,
    FumisResponseError,
    FumisStoveOfflineError,
)

try:
    async with Fumis(mac="AABBCCDDEEFF", password="1234") as fumis:
        await fumis.turn_on()
except FumisAuthenticationError:
    # Invalid MAC address or PIN (HTTP 401)
    ...
except FumisStoveOfflineError:
    # WiRCU not connected to cloud (HTTP 404)
    ...
except FumisConnectionTimeoutError:
    # Request timed out
    ...
except FumisConnectionError:
    # Any connectivity issue (timeout, DNS, HTTP error)
    ...
except FumisError:
    # Any Fumis-specific error
    ...

Exception hierarchy:

FumisError
├── FumisConnectionError
│   └── FumisConnectionTimeoutError
├── FumisResponseError
├── FumisAuthenticationError
└── FumisStoveOfflineError

Status codes use proper Python enums, booleans where they make sense:

from fumis import StoveStatus

info.controller.stove_status == StoveStatus.COMBUSTION  # True
info.controller.on                                      # True
info.controller.eco_mode.enabled                        # False

# Unknown values from the API are handled gracefully
StoveStatus(999)  # StoveStatus.UNKNOWN (never crashes)

This repository keeps a change log using GitHub's releases functionality. The format of the log is based on Keep a Changelog.

Releases are based on Semantic Versioning, and use the format of MAJOR.MINOR.PATCH. In a nutshell, the version will be incremented based on the following:

• MAJOR: Incompatible or major changes.
• MINOR: Backwards-compatible new features and enhancements.
• PATCH: Backwards-compatible bugfixes and package updates.

This is an active open-source project. We are always open to people who want to use the code or contribute to it.

We've set up a separate document for our contribution guidelines.

For in-depth API documentation and reverse engineering notes, see RESEARCH.md.

Thank you for being involved! 😍

The easiest way to start, is by opening a CodeSpace here on GitHub, or by using the Dev Container feature of Visual Studio Code.

This Python project is fully managed using the Poetry dependency manager. But also relies on the use of NodeJS for certain checks during development.

You need at least:

• Python 3.11+
• Poetry
• NodeJS 24+ (including NPM)

To install all packages, including all development requirements:

npm install
poetry install

As this repository uses the prek framework, all changes are linted and tested with each commit. You can run all checks and tests manually, using the following command:

poetry run prek run --all-files

To run just the Python tests:

poetry run pytest

The original setup of this repository is by Franck Nijhof.

For a full list of all authors and contributors, check the contributor's page.

This project is an independent, community-driven effort. It is not affiliated with, endorsed by, or supported by Fumis (ATech elektronika d.o.o.) or any stove manufacturer. All product names, trademarks, and registered trademarks are property of their respective owners.

This library was developed by observing network traffic from devices we own, using publicly available service manuals, and building on existing community integrations. No access controls were bypassed and no proprietary code was used. This work is done for interoperability purposes, protected under EU law including the Software Directive (2009/24/EC), the Data Act (2023/2854), and the GDPR. See RESEARCH.md for the full legal basis and methodology.

Use this software at your own risk. The authors are not responsible for any damage to your stove, property, or person resulting from the use of this library. Pellet stoves involve fire and heat; always follow your manufacturer's safety guidelines.

MIT License

Copyright (c) 2019-2026 Franck Nijhof

Permission is hereby granted, free of charge, to any person obtaining a copy of this software and associated documentation files (the "Software"), to deal in the Software without restriction, including without limitation the rights to use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of the Software, and to permit persons to whom the Software is furnished to do so, subject to the following conditions:

The above copyright notice and this permission notice shall be included in all copies or substantial portions of the Software.

THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.