LEVOIT OasisMist™ 4.5L (LUH-O451S-WEU) partially supported

[chemelli74]

Hi,

device works fine but unfortunately is only partially supported.
Missing features compared to the Vsync mobile app:

• Auto-off: this is a on/off switch
• Night light: this is a on/off switch
• Night light color: you can pick up any color in the RGB pallete
• Timer
• Schedules

Non working features:

• Night mode:
  2025-12-31 17:05:52.633 WARNING (MainThread) [pyvesync.devices.vesynchumidifier] OasisMist™ 4.5L for LUH-O451S-WEU API from set_humidity_mode returned error code: 11000000, message: request_error - Invalid bypass parameter - Mode value invaild! - Mode value invaild!

Here the response from from Home Assistant debug log:

Response Body:
 {
  "traceId": "1767196882",
  "code": 0,
  "msg": "request success",
  "module": null,
  "stacktrace": null,
  "result": {
    "traceId": "1767196882",
    "code": 0,
    "result": {
      "enabled": false,
      "mist_virtual_level": 9,
      "mist_level": 3,
      "mode": "auto",
      "water_lacks": false,
      "water_tank_lifted": false,
      "humidity": 38,
      "humidity_high": false,
      "display": false,
      "warm_enabled": false,
      "warm_level": 0,
      "automatic_stop_reach_target": false,
      "configuration": {
        "auto_target_humidity": 50,
        "display": false,
        "automatic_stop": true
      },
      "extension": {
        "schedule_count": 0,
        "timer_remain": 0
      },
      "rgbNightLight": {
        "action": "off",
        "colorMode": "color",
        "speed": 0,
        "brightness": 40,
        "red": 18,
        "green": 102,
        "blue": 1,
        "colorSliderLocation": 42
      }
    }
  }
}

[cdnninja]

The top section is mostly for the HA integration rather than the library. Do you have a drop down menu for the night light that can turn it on and off?

As for those other top ones, which do you intend to use? What do you find most value in?

[chemelli74]

Hi, thx for the very quick reply !

This is the device view in Home Assistant:

I would say to start with:

• Auto-off: this is a on/off switch
• Night light: this is a on/off switch
• Night light color: you can pick up any color in the RGB pallete

Thank you !

[cdnninja]

Night light will be a drop down menu since that is needed for other device and already exists. For some reason it doesn't expose for this one which is most likely a library issue. I have added this PR for auto off: home-assistant/core#160070 if you could test for your model that would be great! I have tested this on my 300.

[webdjoe]

Are you setting sleep mode with the set_humidity_mode?

The EU model is different from the US model, so I'll need capture packets to be able to add the functionality. You can follow the directions here https://webdjoe.github.io/pyvesync/latest/development/capturing/ or you can share the device temporarily with me so I can capture packets. Message me on discord and I'm happy to assist further homefire1608

[chemelli74]

Are you setting sleep mode with the set_humidity_mode?

The EU model is different from the US model, so I'll need capture packets to be able to add the functionality. You can follow the directions here https://webdjoe.github.io/pyvesync/latest/development/capturing/ or you can share the device temporarily with me so I can capture packets. Message me on discord and I'm happy to assist further homefire1608

Thx!

[cdnninja]

Set_mode:

https://github.com/home-assistant/core/blob/2b10dc454542abdc01de31330a3e09da221eebcd/homeassistant/components/vesync/humidifier.py#L158-L159

[chemelli74]

Night light will be a drop down menu since that is needed for other device and already exists.

I think it should be a light with on/off and RGB colors ;-)

For some reason it doesn't expose for this one which is most likely a library issue.

Is the node in my log the expecred one ? Didn't get time to investigate or debug myself.

I have added this PR for auto off: home-assistant/core#160070 if you could test for your model that would be great! I have tested this on my 300.

Thx, works perfectly !

[chemelli74]

Just noticed that #297 and #484 may apply here as well.

My device has manual, auto and warm (as an alternative to fog) settings.
No sleep.

[ro2342]

I confirm that I can't also use the light feature. It's a miss.

I'm using Home Assistant Container 2026.1.0

Device info
LUH-O451S-WEU
by VeSync

[webdjoe]

I am waiting on device captures, because this is different than the US model. If you want to help out, you can follow the directions here https://webdjoe.github.io/pyvesync/latest/development/capturing/ or you can share the device temporarily with me so I can capture packets. Message me on discord and I'm happy to assist further homefire1608

[MangelSpec]

Night light will be a drop down menu since that is needed for other device and already exists.

I think it should be a light with on/off and RGB colors ;-)

For some reason it doesn't expose for this one which is most likely a library issue.

Is the node in my log the expecred one ? Didn't get time to investigate or debug myself.

I have added this PR for auto off: home-assistant/core#160070 if you could test for your model that would be great! I have tested this on my 300.

Thx, works perfectly !

Hey,

I ran into the same device (LUH-0451S-WEU) and implemented support on my side based on observed behavior and Home Assistant output.

For anyone interested, there is a working reference implementation available:

• pyvesync changes (PR):
#502

• Home Assistant vesync integration (temporary fork):
https://github.com/MangelSpec/core

The core fork includes a short Fork Notice in the README with simple instructions on how to try the modified vesync component locally (via custom_components), without replacing the full Home Assistant installation.

I’m aware that HTTP captures are preferred for upstreaming.
If someone has the time to provide those captures, they could help refine or improve the implementation further.

For now, this works in practice and can be tested by anyone interested.

No pressure at all - happy to adjust anything if needed as said in the PR.
Thanks a lot for maintaining pyvesync

[ro2342]

Night light will be a drop down menu since that is needed for other device and already exists.

I think it should be a light with on/off and RGB colors ;-)

For some reason it doesn't expose for this one which is most likely a library issue.

Is the node in my log the expecred one ? Didn't get time to investigate or debug myself.

I have added this PR for auto off: home-assistant/core#160070 if you could test for your model that would be great! I have tested this on my 300.

Thx, works perfectly !

Hey,

I ran into the same device (LUH-0451S-WEU) and implemented support on my side based on observed behavior and Home Assistant output.

For anyone interested, there is a working reference implementation available:

• pyvesync changes (PR): #502

• Home Assistant vesync integration (temporary fork): https://github.com/MangelSpec/core

The core fork includes a short Fork Notice in the README with simple instructions on how to try the modified vesync component locally (via custom_components), without replacing the full Home Assistant installation.

I’m aware that HTTP captures are preferred for upstreaming. If someone has the time to provide those captures, they could help refine or improve the implementation further.

For now, this works in practice and can be tested by anyone interested.

No pressure at all - happy to adjust anything if needed as said in the PR. Thanks a lot for maintaining pyvesync

I can confirm it is working on Installation method
Home Assistant Container - Core 2026.1.0

[chemelli74]

• Home Assistant vesync integration (temporary fork): https://github.com/MangelSpec/core

@MangelSpec: works fine, thx for your work !

Can I suggest to open a PR in HA core for adding "Warm mist level" ?
Nothing form the library is preventing it's adidtion.

Note: when you use translation_key, you don't need name and icon as those are picked up from strings.json and icons.json

[chemelli74]

Hi @webdjoe, would you mind releasing a new version of the library so we can integrate the changes into the Home Assistant core? :-)

Thanks for considering it.