Stiebel Eltron ISG
pail23/stiebel_eltron_isg_component · v2026.9
Stiebel Eltron ISG integration for Home Assistant
In Apple Home through HomeKit Bridge
What HomeKit Bridge makes of each kind of entity this integration creates, read from its source code. A device only gets the ones that apply to it.
| Entity | Shows up as | Note |
|---|---|---|
switch | Switch or outlet | |
climate | Thermostat | |
binary_sensor | Sensor (motion, contact, leak, smoke…) | |
sensor | Sensor (temperature, humidity, air quality…) | |
button | Button (as a switch) | |
select | Mode picker (as switches) |
What people report
Modbus access to Stiebel Eltron heat pumps through an ISG gateway, covering WPM, WPM 3i and LWZ families. 2026.7.1 broke several LWZ/THZ owners; WPM G support is still being scoped.
- Works4
- Requested1
| Device | In Home Assistant | In Apple Home | What they said | Source |
|---|---|---|---|---|
| Stiebel Eltron THZ 404 sol / LWZ 404 SOL | Works Local | Modbus exception after 2026.7.1; issue closed as fixedSaved copy… has the answer in it: `input block read at address 3679 (count 19) returned Modbus exception code 2`. That is the same failure as #599, where two other LWZ owners report the identical address and count (an LWZ 403 sol and an LWZ 5s plus). Worth following that issue rather than this one, so the discussion stays in one place. Easy to miss, for what it is worth: #599 has address 5219 in its title, which is what WPM and some LWZ machines fail on, so searching for your own 3679 would not have found it. One detail worth correcting, because it points at the wrong culprit: the jump from 2026.7 to … Excerpt saved from GitHub on 2026-10-23. | Issue #601 · 2026-07 | |
| Stiebel Eltron THZ 504 | Works Local | Same 2026.7.1 failure reported; closed as fixedSaved copySimilar issue with my THZ 504 and ISG connect - tried to rollback to last working version (2026.2) but did not work. Deleted the whole HACS ISG module and re-installed 2026.2 still did not work. Excerpt saved from GitHub on 2026-10-23. | Issue #601 · 2026-07 | |
| Stiebel Eltron WPL A07 HK230 Premium | Works Local | Same 2026.7.1 failure reported; closed as fixedSaved copySame issue with my heatpump (WPL A07 HK230 Premium). Rolled back to 2026.2 Excerpt saved from GitHub on 2026-10-23. | Issue #601 · 2026-07 | |
| Stiebel Eltron WPM 3i controller | Works Local | Dedicated implementation with its own Modbus API mergedSaved copySummary by Sourcery Add dedicated support for the WPM 3i controller model with its own Modbus API, data coordinator, and tailored entity sets, while refactoring model handling across the integration. New Features: - Expose WPM 3i-specific system value sensors, binary sensors, climate entities, and number entities based on a new Modbus API definition. - Introduce a separate WPM 3i data coordinator that uses the dedicated WPM 3i Modbus API for updates and writes. Enhancements: - Refine controller model handling by using the ControllerModel enum throughout and adding a model_name helper for … Excerpt saved from GitHub on 2026-10-23. | PR #579 · 2026-07 | |
| Stiebel Eltron WPM G controller (WPE-I 33-87 H 400 Premium) | Requested Local | Read-only alpha being scoped; register map differs from ISGSaved copyContext Two discussions now concern WPM G, but they appear to expose different Modbus surfaces and may require different architectural decisions. - #679 covers a WPE-I 33-87 H 400 Premium connected through an ISG. The reporter supplied STIEBEL ELTRON's ISG Modbus documentation, whose chapter 9 defines dedicated WPM G input and holding register blocks for a primary and up to five secondary heat pumps. The reporter can already read values from those registers and may be able to provide hardware-backed captures. - #585 covers a newer WPE-I 07.1 H Plus with an internal WPM G. Its documentation … Excerpt saved from GitHub on 2026-10-23. | Issue #684 · 2026-09 |
Gathered from GitHub issues, pull requests, discussions and docs, and from r/homeassistant. These are individual reports, so check the linked thread and the date before you buy.
How it connects
Local polling
Talks to the device on your network, asking it for updates every so often.
Found automatically over
- DHCP
Details
| Installs (analytics) | 906 (0.13%) |
|---|---|
| GitHub stars | 106 |
| Latest version | 2026.9 (2026-10-18) |
| Set up in the UI | Yes |
| Maintainers | @pail23 |
| License | MIT |
In ReReHome
Whatever HomeKit Bridge shares reaches Apple Home as normal HomeKit accessories behind your Home Assistant bridge, so ReReHome shows and controls them like any other.
Bridges get their own settings page listing the accessories behind them.
