DucoBox Energy

Use cases

• Monitor indoor CO2 and relative humidity levels on a live dashboard to verify ventilation performance for your customer.
• Create an alert when supply air temperature deviates from the target setpoint for more than 15 minutes.
• Remotely adjust ventilation positions and mode timing without an on-site visit.
• Track daily flow rates versus target levels to identify underperforming zones or blocked valves.
• Log outdoor and extract temperatures over time to optimize energy recovery efficiency.
• Set up a notification when the daily write command limit drops below a safe threshold.

Installation

1. 1Ensure the DucoBox Energy unit is equipped with a connectivity board that enables Modbus TCP communication.
2. 2Connect the DucoBox to the same local network as your ModbusCloud gateway (MCG or MLP series) using an Ethernet cable.
3. 3Verify that the DucoBox is running firmware compatible with API v2.5 and note the unit's IP address and Modbus TCP port.
4. 4In the ModbusCloud platform, import the DucoBox Energy template and assign it to the correct gateway.
5. 5Configure the IP address and port of the DucoBox in the gateway's Modbus TCP connection settings.
6. 6Confirm that readings such as ventilation status, CO2 values, and temperatures appear correctly on the ModbusCloud dashboard.

Things to watch for

01

Why do some registers return unexpected values when read and written simultaneously?

Registers at addresses like 100, 102, 103, 104, and 105 are holding registers used for both reading and writing. Always read after a write operation to confirm the value was accepted. Avoid simultaneous read and write polling on these addresses.

02

My write commands are being rejected during the day. What is going on?

The DucoBox Energy firmware enforces a daily limit on write commands. Check register address 31 to see how many writes remain. Reduce the frequency of write operations in your automations to stay within the allowed budget.

03

I cannot establish a Modbus TCP connection to the DucoBox. What should I check?

Confirm that the connectivity board is installed and powered. Verify the DucoBox IP address and that it is reachable from the gateway's network. Check that no firewall rules are blocking the Modbus TCP port (default is typically 502).

04

Which DucoBox models are supported by this template?

This template supports the DucoBox Energy Comfort, Comfort Plus, Premium, and Sky models, provided they are equipped with a connectivity board and run firmware supporting API v2.5.

Registers (40)

40 read / 9 write

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