Domekt R 400 V

Use cases

• Boost ventilation when a CO2 sensor in a busy living room exceeds a threshold, using a ModbusCloud automation.
• Switch to Away mode automatically when nobody is home based on a presence sensor.
• Log real-time heat recovery efficiency to verify the unit reported value under different outdoor temperatures.
• Track filter impurity to schedule maintenance before indoor air quality drops.
• Monitor post-heater power draw to quantify the extra electricity consumed during cold weeks.

Installation

1. 1In the Komfovent Domekt web UI, enable Modbus TCP under the network configuration menu.
2. 2Note the unit IP and set a DHCP reservation.
3. 3In ModbusCloud, add a Modbus TCP device at the unit IP, port 502, slave ID 60 (the Komfovent default).
4. 4Import the Domekt R 400 V template. Temperatures and airflow readings appear within one poll.
5. 5If you use Away, Normal, Intensive, Boost scheduling, verify the unit accepts Current Mode writes by changing the mode from the ModbusCloud device detail page.

Things to watch for

01

Outdoor temperature reads as a huge positive number in winter. What is wrong?

The template expects int16 at address 903 for signed negative values. If your setup decoded this as uint16, subfreezing temperatures roll over to 65000+ numbers. Ensure the data type in the ModbusCloud template is int16.

02

Current mode writes do not take effect.

Current mode at address 4 is int32, meaning it needs two consecutive registers for both read and write. If your client only writes a single 16-bit register, the mode change is ignored. The ModbusCloud template handles this correctly by default.

Registers (25)

19 read / 10 write

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