I see no data after connecting. What should I check first?

Verify that the baud rate is set to 19200 and parity to odd (1 stop bit) on both the gateway and the Domeo 210 RD. Also confirm that the RS-485 A and B wires are not swapped.

Some registers seem to overlap. Is that normal?

Yes. Some register addresses appear in both read and write function code groups. The template handles this by using the correct function codes for each operation. Do not manually duplicate these registers.

Can I change heating setpoints remotely?

Yes. The template includes writable registers for pre-heating and post-heating battery temperature setpoints. You can adjust these values directly from the ModbusCloud dashboard.

How do I know if the filter needs replacing?

The template reads the dirty filter alarm register. You can set up an alert in ModbusCloud to notify you when this alarm activates, so you can schedule maintenance before airflow is significantly reduced.

Free Modbus template: S & P DOMEO 210 RD

This template connects to the S&P Domeo 210 RD heat recovery ventilation unit via Modbus RTU. It reads temperatures, fan speeds, bypass and battery status, and provides control over airflow, heating setpoints, and bypass operation. All registers use uint16 format.

Registers (61)

61 read / 15 write

Name	Address	Function	Type	Unit	Access
2 CLP CONTROL	2	FC02	uint16		R/W
5 THAW MODE	5	FC02	uint16		R
7 IMPULSION MOTOR STATUS	7	FC02	uint16		R/W
10 INTERIOR TEMPERATURE PROBE STATUS	10	FC02	uint16		R
11 DISCHARGE TEMPERATURE PROBE STATUS	11	FC02	uint16		R
12 OUTDOOR TEMPERATURE PROBE STATUS R	12	FC02	uint16		R/W
13 STATUS PROBE IMPULSION TEMPERATURE	13	FC02	uint16		R
14 ALARM STATUS OF DIRTY FILTER	14	FC02	uint16		R
6 ENGINE EXTRACTION STATUS	6	FC02	uint16		R/W
2 BATTERY PRE-HEATING R_W 0	2	FC01	uint16		R
3 BATTERY POST-HEATING R_W 0	3	FC01	uint16		R/W
4 POTENTIAL FREE CONTACT CONTROL SELECTION R_W 0	4	FC01	uint16		R/W
6 VERSION SELECTOR R_W 0	6	FC01	uint16		R
7 MODE ACTIVATION R_W 0	7	FC01	uint16		R
8 AUTOMATIC CONTROL BYPASS R_W 0	8	FC01	uint16		R/W
9 BYPASS MANUAL R_W 0	9	FC01	uint16		R/W
12 DIRTY FILTER ALARM RESET (BY TIME)	12	FC01	uint16		R
13 RESTORE FACTORY PARAMETERS W	13	FC01	uint16		R
1 VERSION R	1	FC01	uint16		R
6 SOFTWARE VERSION CENTRAL UNITY	6	FC04	uint16		R
7 REMOTE SOFTWARE VERSION	7	FC04	uint16		R
8 CONSOLE PROGRAMMING SOFTWARE VERSION	8	FC04	uint16		R/W
9 TYPE OF DOUBLE FLOW	9	FC04	uint16		R/W
10 TIPE OF REGULATION	10	FC04	uint16		R/W
12 FLOW OFFSET	12	FC04	uint16		R
13 MINIMUM FLOW	13	FC04	uint16		R
14 TIMED HIGH FLOW 1_2H _ BOOST	14	FC04	uint16		R
15 HIGH FLOW _ FREE COOLING	15	FC04	uint16		R/W
16 ACTUAL FLOW	16	FC04	uint16		R/W
17 MEASURED TENSION 0-10V	17	FC04	uint16	V	R/W
19 EXTRACTION ENGINE REVOLUTIONS	19	FC04	uint16	rpm	R
20 IMPULSE ENGINE REVOLUTIONS	20	FC04	uint16	rpm	R
21 TEMPERATURE INT	21	FC04	uint16	°C	R
22 TEMPERATURE EXT	22	FC04	uint16	°C	R
23 TEMPERATURE Tex	23	FC04	uint16	°C	R
24 IMPULSION TEMPERATURE	24	FC04	uint16	°C	R
25 BYPASS STATE	25	FC04	uint16		R
26 BATTERY STATUS PREHEATING	26	FC04	uint16		R
27 POST HEATING BATTERY STATUS	27	FC04	uint16		R
37 ALARM TIME OF DIRTY FILTER	37	FC04	uint16	h	R
36 TEMPERATURE Tin BATTERY PREHEATING	36	FC04	uint16	°C	R
38 TEMPERATURE Tout PREHEATING BATTERY	38	FC04	uint16	°C	R
39 TEMPERATURE Tin POST HEATING BATTERY	39	FC04	uint16	°C	R
40 TEMPERATURE Tout POST HEATING BATTERY_	40	FC04	uint16	°C	R
0 INTERFACE MODBUS NODE	0	FC03	uint16		R
1 BAUDRATE MODBUS	1	FC03	uint16		R
8 SELECTION OF FLOW OFFSET	8	FC03	uint16		R
9 LOW FLOW SELECTION	9	FC03	uint16		R
10 SELECTION OF TIMED HIGH FLOW 1_2 H _ BOOST	10	FC03	uint16		R
11 HIGH FLOW RATE SELECTION _ FREECOOLING	11	FC03	uint16		R/W
15 FLOW SETPOINT	15	FC03	uint16		R
16 MINIMUM SETPOINT IN 0‐10V_	16	FC03	uint16	V	R
17 MAXIMUM SETPOINT IN 0‐10V	17	FC03	uint16	V	R
22 BYPASS AUTO: Text MINIMUM	22	FC03	uint16	°C	R
23 BYPASS AUTO: MINIMUM Tint_	23	FC03	uint16	°C	R
24 TIME BYPASS MANUAL	24	FC03	uint16	min	R
25 PRE-HEATING BATTERY Tº ON	25	FC03	uint16	°C	R
26 PRE-HEATING BATTERY Tº OFF	26	FC03	uint16	°C	R
27 PRE-HEATING BATTERY CONSTANT Tº	27	FC03	uint16	°C	R
28 POST-HEATING BATTERY CONSTANT Tº	28	FC03	uint16	°C	R
31 TIME SELECTION ALARM OF DIRTY FILTER	31	FC03	uint16	h	R

S & P DOMEO 210 RD

Overview

Key readings

Available commands

Use cases

Installation

Things to watch for

Registers (61)

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