[App][Pro] LG Modbus

This app ONLY works with MODBUS enable LG devices, these are normally the AWHP pro installer devices. Commercial devices are more likely to use only LG Thinq (ook at the apps that support those). With these modbus devices the modbus tends to have more data than any Thinq support does. And its fully local. It also allows for more live data.

Monitor and control your LG Air-to-Water Heat Pump directly from Homey — no cloud, no delays. This app communicates locally over Modbus TCP through an RS485-to-TCP gateway, giving you fast, reliable access to your heat pump’s data and controls.

What you can do:

  • Switch heating/cooling on or off and set operation mode (Heat, Cool, Auto)
  • Adjust water target temperature and DHW (hot water) target temperature
  • Monitor live temperatures: water outlet, water inlet, outdoor, room, DHW tank, and backup heater
  • Track energy usage: electrical power consumption, thermal output, and real-time COP
  • View system status: compressor, water pump, defrost cycle, and outdoor unit activity
  • Control DHW heating, silent mode, and temperature control method
  • Get notified on errors with automatic alarm detection and error codes
  • Build automations with flow triggers, conditions, and actions for all key parameters

Requirements:

  • LG Air-to-Water Heat Pump with Modbus RTU support
  • RS485-to-TCP serial gateway (like Elfin EW-11 or compatible) connected to the heat pump’s Modbus port
  • Homey Pro with local network access to the gateway

Try it now:

[Test channel] LG Modbus AWHP | Homey

nice APP!

Do you have future plans to make a turtorial how to configure it? i use now the LG Thinq APP for my heatpump, want to try this one :slight_smile:

Do you know how to add the wiring to unlock the ck modbus? And how to setup a modbus serial to IP gateway? Because I am not going to give modbus wiring tutorials for your device because you might damage it and then blame me :winking_face_with_tongue:

Will it work with a self-hosted Homey system (Raspi 4)?
I’d like to try it with my LG Therma V R290 (14 kW) and that adapter: Amazon.de

Thx in advance!

I see no reason it won’t.

Try Gemini Pro to let you help at installing it!
I managed to get it running today with it and I’m very happy with the app.
For now I can’t see the electrical power, maybe I need a sensor more or so…

It worked, very nice app! Thank you.
Is there a way, that I can see the electrical power my LG heatpump uses?

I read a non documented register for the values. These where listed by some testers but most claim they are non existing. So I think these regsiters are only available in some devices. IN mine they are, and this app reads them (not sure how well I trust them but hey good indication) but if they remain still in your device I have no way to find if or what registers their might be.

So far LG seems rather stable in the modbus klifecycle, adding features not mixing them up, but their documentation is not so good and often false. so….

i thought it wil only cost 30 minuts to install, but after 4 hours i made it! thnx. hopefully i can modify the settings when to heat and cool my house and on which setting/modus. :slight_smile: For the others, chatGPT and Gemini helped me alot.

Hi,

I have since a couple of days the modbus. Since then i have so now and then CH03 error. Its something with the communication between the thermostat and the monobloc. Ive did some research on tweakers. It looks like that the modbus pulls to much data from the monobloc in to short of time. Then the error CH03 appears.

Do you recognize this problem? And what can i do about it?

hmm, yes and I tweaked it so it didnt anymore. There are two mechanism, when you connect a modbus and then STOP polling, the thermostat goes into error. I implemented a keep alive for that.
Next dont overload it, so I ensure I dont poll to much (isnt that a setting?)

Can you share what you changed? I have changed also some parameters. But still having this issue

I mean in my app, so those are there already.
There is a polling interval setting, it’s default on 60 seconds. You can try to increase that.
Like I said LG uses a demon to bait the modbus controller n is still there, if your model uses one that is shorter than mine you might see this