Jaano RosinandClaude Opus 5
5cc45b97bc
The heat limit registers on heat pumps using EMS_DEVICE_FLAG_HEATPUMP
(product 172/173) are bytes 2/3/4 of telegram 0x0492, read as a direct
index into enum_maxHeat. That table has only six entries, so any unit
whose auxiliary electric heater goes above 9 kW reports an index the
table cannot resolve.
Nothing bounds-checks the raw byte on the way in, and every render path
guards on `value < options_size`, so an out-of-range index is dropped
silently: no value is published to MQTT, the API omits the field, Home
Assistant shows `unknown`, and nothing appears in the log. Helpers::
value2enum stops at the same boundary, so the value cannot be written
back from EMS-ESP either, leaving the entity permanently stuck.
Measured on a Bosch Compress 7000i AW (CS7000iAW 13 OR-T, product 172)
with a 15 kW auxiliary heater, by setting each limit from the unit's own
display and reading telegram 0x0492 back:
display 12 / 9 / 6 kW -> 0x0492 data: 03 00 06 05 04
raw kW note
0 0 agrees with the existing table
1 2 not offered by this heater
2 3 not offered by this heater
3 4 not offered by this heater
4 6 agrees with the existing table
5 9 agrees with the existing table
6 12 new
7 15 new
Indices 0, 4 and 5 match what EMS-ESP already decodes, which confirms the
existing entries and their ordering; the table was correct, just short.
The 2 kW and 4 kW entries belong to the 4-stufig (2/4/6/9 kW) heater
variant described in the HPC 410 service manual section 4.2.2, so a
3 kW-stepped heater simply skips them and walks 0, 3, 6, 9, 12, 15 kW,
i.e. raw 0, 2, 4, 5, 6, 7. The same sparse pattern is already encoded for
CS6800 devices in Boiler::process_HpHeaterConfig, which maps raw
{0, 2, 4, 5} onto {0, 3, 6, 9} kW.
Only devices carrying EMS_DEVICE_FLAG_HEATPUMP are affected; CS6800
devices use enum_maxHeat1/enum_maxHeat2 and are unchanged. Verified with
the standalone build: `test entity_dump` differs from the committed
docs/dump_entities.csv in exactly the six maxheat rows of products 172
and 173, and nowhere else.
Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
EMS-ESP
EMS-ESP is an open-source firmware for the Espressif ESP32 microcontroller to communicate with EMS (Energy Management System) compatible equipment from manufacturers such as Bosch, Buderus, Nefit, Junkers, Worcester, Sieger, elm.leblanc and iVT.
It requires a small circuit to interface with the EMS bus which can be purchased from https://bbqkees-electronics.nl. These gateways are tested thoroughly and certified to work with EMS-ESP.
📦 Key Features
- Compatible with EMS, EMS+, EMS2, EMS Plus, Logamatic EMS, Junkers 2-wire, Heatronic 3 and 4
- Supporting over 120 different EMS compatible devices such as thermostats, boilers, heat pumps, mixing units, solar modules, connect modules, ventilation units, switches and more
- Easy to add external Temperature and Analog sensors that are attached to GPIO pins on the ESP32 board
- A multi-user, multi-language web interface to change settings and monitor incoming data
- A simple to use console, accessible via Serial/USB or Telnet for advanced operations and detailed monitoring
- Native integration with Home Assistant, Domoticz, openHAB and Modbus
- Easy setup and install with automatic updates
- Simulation of remote thermostats
- Localized in 11 languages, and customizable to rename any device or sensor
- Extendable by adding own custom EMS entities
- Expandable via adding user-built external modules
- A powerful Scheduler to automate tasks and trigger events based data changes
- A Notification service to alert you of important events
🚀 Installing
Head over to the Installation Guide section of the documentation for instructions on how to install EMS-ESP.
📋 Documentation
Visit emsesp.org for more details on how to setup and configure EMS-ESP. You'll also find more a collection of example configuarations, Frequently Asked Questions and Troubleshooting tips.
💬 Getting Support
To chat with the community reach out on our Discord Server.
If you find an issue or have a request, see the Getting Support section of the documentation. Note if you are using a non-BBQKees EMS gateway, you may need to contact the manufacturer for support.
🎥 Live Demo
To see a live demo go to demo.emsesp.org. Pick a language and use any username and password to log in. Note whast you're seeing is static example data so not all features are operational.
💖 Contributors
EMS-ESP is a project originally created by proddy and maintained by the ems-esp community.
If you like EMS-ESP, please give it a ✨ on GitHub, or even better fork it and contribute. You can also offer a small donation. This is an open-source project maintained by volunteers, and your support is greatly appreciated.
📦 Building
See the Building the firmware guide in the documentation for instructions on how to build EMS-ESP from this source code.
📢 Libraries used
- esp8266-react originally by @rjwats for the core framework that provides the Web UI, which has been heavily modified
- uuid-* from @nomis. The console, syslog, telnet and logging are based off these awesome open source libraries
- ArduinoJson for all the JSON processing
- espMqttClient for the MQTT client
- ESPAsyncWebServer and AsyncTCP for the Web server
📜 License
This program is licensed under GPL-3.0
Screenshots
Web Interface
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Telnet Console
Home Assistant
