I was looking to integrate my new Bosch heatpump with Homey, but unfortunately this was not possible at all as Bosch has currently no API set which can be easily used. They annouced a REST API set for later this year.
I decide to purchase the BBQKees device which is based on the EMS-ESP project.
I was really impressed by the quality and functionality of this device. It finds all components connected to the Bosch EMS bus like the heatpump, thermostat, mixer, UI800 and publishes nearly 300 values via REST, MQTT and Modbus TCP. It also can set certain parameters via those protocols.
There is a Homey integration as a base with another heapump model to integrate via REST. As I am not a developer I decided not to go this way and fork this driver. If you are interested : GitHub - angas/se.assermark.ems-esp: Homey Pro app for EMS-ESP
I integrated BBQKees via EMS Broker/Client/Hub. Unfortunately MQTT Discovery via homeassistant discover protocol is not supported, only homie discovery. So I had to configure the certain parmeters manually which took some hours do to the lack of documentation and stability of the the current community version which hopefully improves over time.
At the end I am quite happy what I have achieved now and I am looking to improve the integration further once MQTT is a bit more stable.
