Immergas Dominus

Version: 0.3.0 Author: JoTu (github.com/jotuera)

Home Assistant custom integration for local control of an Immergas boiler through the Dominus Wi-Fi module — no cloud, no MQTT. Home Assistant talks directly to the Dominus module over local TCP (default port 2000) using the module MAC and password.

Tested on Immergas Magis Combo and Magis Pro (Magis PRO COMBO V2, MPROCOMBOV2 configuration). Other Immergas models that use the same Dominus module may work, but are not verified.

The interface is English by default, with a full Polish translation. The integration version and author are also shown on each Dominus device page in Home Assistant (the Firmware field, e.g. 0.3.0 — JoTu).

Features

• Local TCP connection, config flow (host/IP, port, Dominus MAC, Dominus password).
• No cloud dependency, no MQTT, no sniffer, no debug/raw-PDU entities.
• Last-known-good caching and dynamic polling — only PDUs of enabled entities are read.

Main device

• Sensors: outdoor temperature (3002, 0xFF = no probe), DHW tank temperature (3016).
• Operation mode select (2000): Standby / Summer / Cooling / Winter.
• DHW target (2095) and DHW thermostat.
• Boiler fault reporting (like the Dominus app): fault code (2100), fault description (English text from the decoded Dominus app fault table, 114 codes), Boiler fault (binary, problem) and Reset available (binary, 2101 bit 1).

Zone 1 (and disabled-by-default Zone 2 / Zone 3)

• Room temperature, heating target, heating curve offset (U03), comfort/eco heat & cool, humidity and flow setpoints (sliders), plus a heating thermostat.
• Per-zone registers are offset by +10 per zone (Zone 1 2011/2015/2210…, Zone 2 2021/2025/2220…, Zone 3 2031/2035/2230…). Zone 2/3 devices are disabled by default; enable the device to bring all its entities online.

Heating schedule (disabled by default)

• 4 shared day profiles (Cal 1–4) × 4 comfort periods, each a start/end time (2310–2347, high byte = hour, low byte = minute; 24:00 shown as 23:59).
• Weekday → profile assignment for Zone 1 (2410–2416), plus a Set the same profile for all days shortcut.

Installation

HACS (custom repository)

1. HACS → Integrations → ⋮ → Custom repositories.
2. Add https://github.com/jotuera/immergas-dominus, category Integration.
3. Install Immergas Dominus, restart Home Assistant.
4. Settings → Devices & services → Add integration → Immergas Dominus.

Manual

Copy custom_components/immergas_dominus into your Home Assistant config/custom_components/ directory, restart Home Assistant, then add the integration as above.

The first local TCP session can be rejected by the Dominus module (e.g. just after the mobile app was used); the integration creates the entities anyway and values appear once the module accepts the session.

Notes

• Fault descriptions are extracted from the decoded Dominus app label table (LBL-WFC01_IM_MBUS_MPROCOMBOV2.json, English fields), the same source used for the D+/D- and T-/T+ bus tooling.
• Registers confirmed only on the D+/D- bus (schedule, fault flags) are cross-checked but may need verification over TCP AUTH on other models.

Changelog

0.3.0

• First public GitHub release. English by default (device names, entities, and English boiler fault descriptions from the Dominus app), Polish provided as a translation.
• HACS-ready layout (custom_components/, hacs.json), MIT license, author metadata.

0.2.x

• 0.2.10 — "Set the same profile for all days" schedule shortcut.
• 0.2.9 — CO heating schedule (32 time entities + 7 weekday selects).
• 0.2.8 — Boiler fault reporting (code, description, active, reset-available).
• 0.2.7 — Heating curve offset (U03) for Zone 2/3.
• 0.2.6 — Zone 2/3 disabled at the device level; setpoints as sliders.
• 0.2.5 — Zone 2/3 entities; dynamic polling.
• 0.2.4 — DHW entities moved onto the main device.
• 0.2.3 — Outdoor 0xFF = no probe; confirmed operation-mode mapping.
• 0.1.9 — Last-known-good caching, optimistic write updates.

Brand assets

Bundled Home Assistant brand assets live in custom_components/immergas_dominus/brand/. The icon is original project artwork (red background, white thermostat and wireless symbols) and does not copy Immergas/Dominus app artwork.

License

MIT © JoTu. Not affiliated with or endorsed by Immergas.