comfoair/commands/auto

[Flink88]

Bug Report

Hardware

• Board: Waveshare ESP32-S3-RS485-CAN (headless bridge mode)
• Ventilation unit: Zehnder ComfoAir Q350
• Connection: Direct CAN via ComfoNet RJ45

Firmware

• Latest version from main branch (cloned 2026-06-02)

Description

Sending the MQTT command comfoair/commands/auto (payload: on) has no effect on the ventilation unit. The operating_mode sensor remains on limited_manual and the fan speed does not change.

Steps to reproduce

1. Set ventilation to manual mode (speed 1, 2 or 3) via MQTT command — works correctly
2. Publish on to comfoair/commands/auto
3. Wait 10+ minutes
4. comfoair/operating_mode remains limited_manual

Expected behavior

The unit should switch to auto mode, as confirmed by the protocol documentation:
85 15 08 01 = Switch to auto mode (source: michaelarnauts/aiocomfoconnect PROTOCOL-RMI.md)

Observed behavior

• The MQTT message is correctly received by the broker ✅
• The firmware receives the message and calls sendCommand("auto") ✅
• The CAN frame { 0x85, 0x15, 0x08, 0x01 } is sent to the bus ✅
• The Q350 does NOT change its operating mode ❌

Additional notes

• Switching to auto mode works correctly from the physical screen of the Q350
• Switching to manual speeds 0-3 via MQTT works correctly
• Bypass activate/deactivate via MQTT works correctly
• The operating_mode PDO (PDOID 49) correctly reports auto / limited_manual
• When set to auto from the physical screen, comfoair/operating_mode correctly reports auto

Hypothesis

The Q350 may require the command to come from a registered ComfoNet node, or the CAN frame addressing may differ for this specific command. The CanAddress used is (0x11, 0x1, 0, 0, 0, 1, sequence) which is the same for all commands including the working ones.

[vincentmakes]

Fixed and tested on 1.5.1

I have not modified any UI, it's pure command based.

publishing 'on' on comfoair/commands/auto will now work. Selecting any speed on the screen changes the mode to manual temporarily (as per MVHR default behaviour). After 2h it returns to auto.
To switch to manual publish 'on' on comfoair/commands/manual