HomeAssistant Modbus configuration for Pichler LG350 Ventilation Units (possible for LG450 too)

lg350.yml

modbus:
  - name: pichlerlg350
    type: tcp
    host: 192.168.44.232
    port: 502
    delay: 2
    message_wait_milliseconds: 30
    binary_sensors:
      - name: "lg350_bypassklappe" # 0.0
        unique_id: "lg350_bypassklappe"
        slave: 20
        address: 20
        input_type: input
        device_class: opening
    switches:
      - name: "lg350_betriebsmodus_sommer"
        slave: 20
        address: 1
        write_type: holding
        command_on: 1 # Sommer
        command_off: 2 # Winter
        verify:
          delay: 1
      - name: "lg350_bypassklappe_force_open"
        slave: 20
        address: 49
        write_type: holding
        # data_type: uint16
        command_on: 2 # Ein/Offen
        command_off: 0 # Normal.  "1" waere Aus/Geschlossen
        verify:
          delay: 1
    sensors:
      - name: "lg350_temp_aussenluft" # 0.0
        unique_id: "lg350_temp_aussenluft"
        unit_of_measurement: "°C"
        slave: 20
        address: 30
        input_type: input
        data_type: int16
        offset: -100
        precision: 1
        scale: 0.1
      - name: "lg350_temp_fortluft" # 3.0
        unique_id: "lg350_temp_fortluft"
        unit_of_measurement: "°C"
        slave: 20
        address: 31 # 30
        input_type: input
        data_type: int16
        offset: -100
        precision: 1
        scale: 0.1
      - name: "lg350_temp_abluft" # 0.2
        unique_id: "lg350_temp_abluft"
        unit_of_measurement: "°C"
        slave: 20
        address: 32 # 31
        input_type: input
        data_type: int16
        offset: -100
        precision: 1
        scale: 0.1
      - name: "lg350_temp_zuluft" # xxx
        unique_id: "lg350_temp_zuluft"
        unit_of_measurement: "°C"
        slave: 20
        address: 33 # 32
        input_type: input
        data_type: int16
        offset: -100
        precision: 1
        scale: 0.1
      - name: "lg350_temp_aussenluft_vhr"
        unique_id: "lg350_temp_aussenluft_vhr"
        unit_of_measurement: "°C"
        slave: 20
        address: 34
        input_type: input
        data_type: int16
        offset: -100
        precision: 1
        scale: 0.1
      - name: "lg350_zuluftdrehzahl"
        unique_id: "lg350_zuluftdrehzahl"
        unit_of_measurement: "rpm"
        slave: 20
        address: 39
        input_type: input
        data_type: int16
      - name: "lg350_abluftdrehzahl"
        unique_id: "lg350_abluftdrehzahl"
        unit_of_measurement: "rpm"
        slave: 20
        address: 40
        input_type: input
        data_type: int16
      - name: "lg350_zuluftstrom"
        unique_id: "lg350_zuluftstrom"
        unit_of_measurement: "m3/h"
        slave: 20
        address: 46
        input_type: input
        data_type: int16
      - name: "lg350_abluftstrom"
        unique_id: "lg350_abluftstrom"
        unit_of_measurement: "m3/h"
        slave: 20
        address: 47
        input_type: input
        data_type: int16
      - name: "lg350_reststandzeit_filter"
        unique_id: "lg350_reststandzeit_filter"
        unit_of_measurement: "h"
        slave: 20
        address: 50
        input_type: input
        data_type: uint16
      - name: "lg350_betriebsmodus_sw"
        unique_id: "lg350_betriebsmodus_sw"
        slave: 20
        address: 1
        input_type: holding
        data_type: uint16
      - name: "lg350_lufstrom_stufe1"
        unique_id: "lg350_luftstrom_stufe1"
        unit_of_measurement: "m3/h"
        slave: 20
        address: 9
        input_type: holding
        data_type: int16
      - name: "lg350_lufstrom_stufe2"
        unique_id: "lg350_luftstrom_stufe2"
        unit_of_measurement: "m3/h"
        slave: 20
        address: 10
        input_type: holding
        data_type: int16
      - name: "lg350_lufstrom_stufe3"
        unique_id: "lg350_luftstrom_stufe3"
        unit_of_measurement: "m3/h"
        slave: 20
        address: 11
        input_type: holding
        data_type: int16
      - name: "lg350_luftstufe"
        unique_id: "lg350_luftstufe"
        slave: 20
        address: 2
        input_type: holding
        data_type: int16
      - name: "lg350_bypassklappe_set"
        unique_id: "lg350_bypassklappe_set"
        slave: 20
        address: 49
        input_type: holding
        data_type: int16
      - name: "lg350_abluftdifferenz_stufe1"
        unique_id: "lg350_abluftdifferenz_stufe1"
        unit_of_measurement: "m3/h"
        slave: 20
        address: 83
        input_type: holding
        data_type: int16
        offset: -500
      - name: "lg350_abluftdifferenz_stufe2"
        unique_id: "lg350_abluftdifferenz_stufe2"
        unit_of_measurement: "m3/h"
        slave: 20
        address: 84
        input_type: holding
        data_type: int16
        offset: -500
      - name: "lg350_abluftdifferenz_stufe3"
        unique_id: "lg350_abluftdifferenz_stufe3"
        unit_of_measurement: "m3/h"
        slave: 20
        address: 85
        input_type: holding
        data_type: int16
        offset: -500

sensor:
  - platform: template
    sensors:
      lg350_luftstufe_render:
        friendly_name: "Luftstufe"
        value_template: >-
          {% set lg350_luftstufe_mapper =  {
          0: 'Standby',
          1: 'Stufe 1',
          2: 'Stufe 2',
          3: 'Stufe 3',
          4: 'Grundlüftung'} %}
          {% set state =  states('sensor.lg350_luftstufe')|int %}
          {{ lg350_luftstufe_mapper[state] if state in lg350_luftstufe_mapper else 'Unknown' }}
      lg350_bypassklappe_set_render:
        friendly_name: "Bypass Klappe Stellung"
        value_template: >-
          {% set lg350_bypassklappe_set_mapper = {
          0: 'Normal',
          1: 'Aus/Geschlossen',
          2: 'Ein/Offen'} %}
          {% set state = states('sensor.lg350_bypassklappe_set')|int %}
          {{ lg350_bypassklappe_set_mapper[state] if state in lg350_bypassklappe_set_mapper else 'Unknown' }}
      lg350_betriebsmodus_sw_render:
        friendly_name: "Betriebsmodus"
        value_template: >-
          {% set lg350_betriebsmodus_sw_mapper = {
          1: 'Sommer',
          2: 'Winter'} %}
          {% set state = states('sensor.lg350_betriebsmodus_sw')|int %}
          {{ lg350_betriebsmodus_sw_mapper[state] if state in lg350_betriebsmodus_sw_mapper else 'Unknown' }}

template:
  - sensor:
      - name: "LG350 Heizleistung"
        unique_id: "lg350_heizleistung"
        state_class: "measurement"
        unit_of_measurement: "W"
        device_class: power
        state: >
          {% set vorlauf = states('sensor.lg350_temp_zuluft') | float (0) %}
          {% set ruecklauf = states('sensor.lg350_temp_abluft') | float %}
          {% set durchfluss = states('sensor.lg350_zuluftstrom') | float %}
          {{ ((vorlauf - ruecklauf) * durchfluss * 0.33  ) | round(1, default=0) }}

Hi @lewurm,
came here via energiesparhaus.at
how did you find the register numbers for rpm values (39,40)? did not find them in the modbus documentation from pichler website
https://www.pichlerluft.at/dezentral-wohnungsweise-lueftungsgeraete.html?file=files/content/downloads/LOGIN/LG%20350_LG%20450_LG%20740_LG%201000%20SK/LIST_Modbus_ES2020_FW_Cv14_LG350_LG450_LG740_LG1000_v14_D-E.xlsx
do you have more registers numbers that are not documented there? :)

Thanks and regards
Stefan

Hey @boxleits,

I don't remember specifically the story behind the rpm values, but some were found be the user berhan in the energiesparhaus.at forum. some values have been figured out by dumping all the modbus registers and cross check the behaviour by changing stuff in the service menu via the touch panel. For example the registers 83-85 have been figured out that way. All registers that I know (and care of) are in this yaml file.

To be honest I haven't seen your linked document so far, how did you find that?! :-) I'm only aware of the KNX one, that partially maps to the modbus layout. This looks super useful, thank you!

The manufacturer's documentation is publicly available:
https://www.pichlerluft.at/ -> Komfort-Service -> Download -> Unterlagen -> Modbuslisten LG-Serie

How did you find the formula to calculate the heating power: (vorlauf - ruecklauf) * durchfluss * 0.33 ?
When I tried to figure out a way to calculate and measure efficiency of the heat exchanger, i learned that i would have to take absolute air humidity levels into account (wet air contains more energy than dry air). That is why i dismissed the idea eventually.

How did you find the formula to calculate the heating power: (vorlauf - ruecklauf) * durchfluss * 0.33 ?

I assumed that 0.33Wh is needed to increase 1 m3 of air by 1 K. But indeed, it ignores humidity.

The manufacturer's documentation is publicly available:
https://www.pichlerluft.at/ -> Komfort-Service -> Download -> Unterlagen -> Modbuslisten LG-Serie

I swear this wasn't there a couple months ago 😅 thank you!!

Forgive my ignorance, but can I save this as lg350.yml and just have an include in configuration.yaml? Or do I have to distribute this to modbus / sensor / template?
Thank you, just received my modbus interface and this helps a lot :-)

@mihu-ov you can copy paste it into your configuration.yaml or you try, as you suggested, to include it. Under Settings -> Devices & Services you should see a ModBus integration then with the entities defined.

FWIW I didn't use the Pichler Modbus device, but just attached it an ESP32 with an RS485 converter to "L11" (see picture). The ESP32 runs Tasmota and uses the the ModBus Bridge feature which makes it available as ModBus TCP, which can be accessed from Home Assistant then.

Thank you, working fine now with a cheap Elfin EE11A Ethernet to RS485 device connected to L11!

Thank you, working fine now with a cheap Elfin EE11A Ethernet to RS485 device connected to L11!

Nice! 🙂