Heatpump Modbus Register 9: Forced Hydraulic Module Rear Electric Heater 1

Technical Definition

The register Forced Hydraulic Module Rear Electric Heater 1 at address 9 is used to monitor forced hydraulic module rear electric heater 1 on the heatpump.

• Protocol: Modbus RTU
• Data Type: U WORD
• Unit:
• Access: Read Only

How to Read (Python pymodbus)

Use this code snippet to read this specific value via RS485:

from pymodbus.client.sync import ModbusSerialClient

client = ModbusSerialClient(method='rtu', port='/dev/ttyUSB0', baudrate=9600)
client.connect()

# Read Forced Hydraulic Module Rear Electric Heater 1 (Address: 9)
# Note: Check if your device uses 0-based or 1-based addressing
result = client.read_input_registers(address=9, count=2, unit=1)

if not result.isError():
    print(f"Raw Value: {result.registers}")
else:
    print("Error reading register")

client.close()

Integration (Home Assistant)

Paste this into your configuration.yaml:

- platform: modbus_controller
  name: "Forced Hydraulic Module Rear Electric Heater 1"
  address: 9
  value_type: U_WORD
  unit_of_measurement: ""

Connection Diagram

Here is the standard RS485 wiring for this configuration:

graph TD
    PLC[Host Controller / Home Assistant]
    Device[heatpump]

    PLC -- "A+ (D+)" --> Device
    PLC -- "B- (D-)" --> Device
    PLC -- GND --> Device

💡 Engineer's Insight

Analysis: Control status for a rear electric heater (binary). Indicates if the heater is forced on or off.

Troubleshooting: Check system commands and logic. Verify heater power supply and internal components. Ensure Temperature setpoints allow for heater activation.