Heatpump Modbus Register 174: Total DHW renewable energy produced for master unit

Technical Definition

The register Total DHW renewable energy produced for master unit at address 174 is used to monitor total dhw renewable energy produced for master unit on the heatpump.

• Protocol: Modbus RTU
• Data Type: U DWORD
• Unit: kWh
• 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 Total DHW renewable energy produced for master unit (Address: 174)
# Note: Check if your device uses 0-based or 1-based addressing
result = client.read_input_registers(address=174, 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: "Total DHW renewable energy produced for master unit"
  address: 174
  value_type: U_DWORD
  unit_of_measurement: "kWh"

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: Total DHW energy (kWh) generated from renewable sources by the master unit. Tracks renewable contribution to DHW heating.

Troubleshooting: Zero suggests no renewable source contribution or an issue with the renewable energy measurement for DHW production.