Does anyone know of a guide to the interconnection technologies used by current Viessmann devices?
My old Viessmann Vitodens 200-W gas condensing system boiler (type WB2C) will soon need to be replaced. The various parts of the system are interconnected using the proprietary KM-Bus 2-wire bus. Works fine but no external connection.
I really wanted to replace it with a Viessmann Vitocal 200-A air source heat pump (ASHP). After a lengthy investigation, I have concluded that even with the UK government grant the disruption and cost are higher than I am prepared to accept. It supports the proprietary KM-Bus so some of the existing system could have been reused. If I later decided to upgrade my MVHR to a Viessmann Vitovent 300-C then that could be connected using Modbus which is also used between the internal and external units of the ASHP. The Vitocal 200-A has a WiFi option for external connection.
So I’m thinking of replacing the old Vitodens 200-W with the latest Vitodens 200-W (type B2HF). Should be simple, right? The latest model uses the proprietary PlusBus 2-wire bus. The wiring can be reused but the KM-Bus devices will need to be replaced with PlusBus devices. It does have integral WiFi for external connection. No Modbus for possible future direct integration with the Vitovent 300-C. The Vitodens 200-W appears to have CAN bus with a very expensive option for a WAGO MB/RTU gateway.
To add to the confusion the Vitodens 200-W (type B2HF) is compatible with the Vitotrol 300-E. This has an encrypted 2.4 GHz low power radio connection to the boiler and an optional 2.4 GHz WiFi connection for automatic software updates. Would be really handy if it is a Matter or Zigbee certified device! However, the low power radio connection could be proprietary.
Is the Vitotrol 300-E low power radio connection the future for connecting Viessmann domestic devices? I see from Funkfernbedienung Vitotrol 300-E that the Vitoair FS ventilation unit is supported (maybe it is an alternative to the Vitovent 300-C)?.
Even if the Vitotrol 300-E was a Zigbee (or Matter) Certified Product there is no guarantee than it could be used by Home Assistant.
It would be interesting to hear from anyone who has experience with the Vitotrol 300-E. Otherwise, I will have to wait until I have a new gas boiler installed and try one myself …
1538 Low power radio (“ZigbeeEnable”) Activation of low power radio. Required for connecting external sensors such as the ViCare climate sensor and remote control units such as the Vitotrol 300-E.
I now have a Viessmann Vitodens 200-W (Type B2HF-19) and a Vitotrol 300-E. The low power radio on both is Zigbee and the EUID and Install Code are available for both devices. nRF Sniffer for 802.15.4 confirms that there is (encrypted) traffic between them on channel 11.
The Add component option in the ViCare App (Version 3.30.0) suggests that only ViCare Smart Climate components (Thermostat, Climate Sensor, Range Extender, …) can be added. I tried adding one of my Danfoss Ally thermostatic valves with the QR Code but it wouldn’t recognise it. Then tried manually inputting the EUID and Install Code which was accepted! Didn’t complete because the device wasn’t in pairing mode. Scope for further experimentation.