Helty VMC Integration for Home Assistant

A clean, modern Home Assistant custom integration for Helty VMC (Flow Plus/Elite) devices.

Credits

Protocol reverse-engineered from the VMC-HELTY-FLOW project by Ing. Danilo Robotti.

Features

• Fan Entity: Control fan speed with preset modes (Speed 1-4, Boost, Night, Free Cooling)
• Sensors:
  • Internal Temperature
  • External Temperature
  • Internal Humidity
  • CO2 (Elite model only)
  • VOC (Elite model only)
  • Current Speed Mode
  • Airflow Rate (m³/h)
• Switches:
  • LED Panel On/Off
  • Sensors On/Off
• Button:
  • Reset Filter Counter

Prerequisites

1. Static IP: Configure your router to assign a static IP to your VMC device
2. Network Access: Ensure Home Assistant can reach the VMC on port 5001
3. Air Guard App: Make sure your VMC is visible in the Helty Air Guard app first

Installation

Method 1: Manual Installation

1. Copy the custom_components/helty_vmc folder to your Home Assistant config/custom_components/ directory:

   config/
   └── custom_components/
       └── helty_vmc/
           ├── __init__.py
           ├── config_flow.py
           ├── const.py
           ├── coordinator.py
           ├── fan.py
           ├── sensor.py
           ├── switch.py
           ├── button.py
           ├── protocol.py
           ├── manifest.json
           ├── strings.json
           └── translations/
               ├── en.json
               └── it.json
   

2. Restart Home Assistant

3. Go to Settings → Devices & Services → Add Integration

4. Search for "Helty VMC"

5. Enter your VMC's IP address and configure options

Method 2: HACS (if published)

1. Add this repository to HACS as a custom repository
2. Install "Helty VMC" integration
3. Restart Home Assistant
4. Configure via UI

Configuration

Option	Default	Description
IP Address	Required	Static IP of your VMC device
Port	5001	TCP port (don't change unless necessary)
Name	Helty VMC	Display name for the device
Update Interval	30	How often to poll the device (seconds)

Usage

Note: See the examples/ folder for complete automation, script, and Lovelace card examples.

Fan Control

The VMC appears as a fan entity with these preset modes:

• speed_1 - Speed 1 (~15 m³/h)
• speed_2 - Speed 2 (~30 m³/h)
• speed_3 - Speed 3 (~45 m³/h)
• speed_4 - Speed 4 (~60 m³/h)
• boost - Boost/Hyperventilation (~80 m³/h)
• night - Night mode (~10 m³/h)
• free_cooling - Free Cooling/Heating (~60 m³/h)

Automation Examples

Set speed based on CO2 levels

automation:
  - alias: "VMC Auto Speed by CO2"
    trigger:
      - platform: numeric_state
        entity_id: sensor.helty_vmc_co2
        above: 1000
    action:
      - service: fan.set_preset_mode
        target:
          entity_id: fan.helty_vmc
        data:
          preset_mode: speed_3

  - alias: "VMC Normal Speed when CO2 OK"
    trigger:
      - platform: numeric_state
        entity_id: sensor.helty_vmc_co2
        below: 800
    action:
      - service: fan.set_preset_mode
        target:
          entity_id: fan.helty_vmc
        data:
          preset_mode: speed_1

Night mode schedule

automation:
  - alias: "VMC Night Mode"
    trigger:
      - platform: time
        at: "22:00:00"
    action:
      - service: fan.set_preset_mode
        target:
          entity_id: fan.helty_vmc
        data:
          preset_mode: night

  - alias: "VMC Day Mode"
    trigger:
      - platform: time
        at: "07:00:00"
    action:
      - service: fan.set_preset_mode
        target:
          entity_id: fan.helty_vmc
        data:
          preset_mode: speed_2

Humidity-based ventilation

automation:
  - alias: "VMC Boost on High Humidity"
    trigger:
      - platform: numeric_state
        entity_id: sensor.helty_vmc_humidity_internal
        above: 70
        for:
          minutes: 5
    action:
      - service: fan.set_preset_mode
        target:
          entity_id: fan.helty_vmc
        data:
          preset_mode: boost

Turn off when away

automation:
  - alias: "VMC Off When Away"
    trigger:
      - platform: state
        entity_id: group.family
        to: "not_home"
        for:
          minutes: 30
    action:
      - service: fan.turn_off
        target:
          entity_id: fan.helty_vmc

Lovelace Card Example

type: entities
title: Helty VMC
entities:
  - entity: fan.helty_vmc
  - entity: sensor.helty_vmc_speed_mode
  - entity: sensor.helty_vmc_speed
  - entity: sensor.helty_vmc_airflow_rate
  - type: divider
  - entity: sensor.helty_vmc_internal_temperature
  - entity: sensor.helty_vmc_external_temperature
  - entity: sensor.helty_vmc_internal_humidity
  - entity: sensor.helty_vmc_co2
  - entity: sensor.helty_vmc_voc
  - type: divider
  - entity: switch.helty_vmc_led_panel
  - entity: switch.helty_vmc_sensors
  - entity: binary_sensor.helty_vmc_filter_warning
  - entity: binary_sensor.helty_vmc_online
  - type: divider
  - entity: button.helty_vmc_reset_filter

Testing the Connection

You can test connectivity to your VMC from the command line:

# Test connection (should return VMGO,...)
echo "VMGH?" | nc YOUR_VMC_IP 5001

# Get sensor data (should return VMIO,...)
echo "VMGI?" | nc YOUR_VMC_IP 5001

# Get device name
echo "VMNM?" | nc YOUR_VMC_IP 5001

Troubleshooting

Cannot connect to VMC

1. Verify the IP address is correct
2. Check that port 5001 is not blocked by firewall
3. Ensure VMC is visible in the Air Guard app
4. Try the nc commands above to test connectivity

Sensors show unavailable

1. The VMC sensors feature might be disabled - use the Sensors switch to enable
2. CO2 and VOC sensors are only available on the Elite model

Filter reset doesn't work

The filter reset command sends the reset signal to the VMC. Verify by checking the Air Guard app.

Protocol Reference

Command	Description
VMGH?	Get fan status
VMGI?	Get sensor readings
VMNM?	Get device name
VMSL?	Get LAN info
VMWH0000000	Set speed 0 (off)
VMWH0000001	Set speed 1
VMWH0000002	Set speed 2
VMWH0000003	Set speed 3
VMWH0000004	Set speed 4
VMWH0000005	Set boost mode
VMWH0000006	Set night mode
VMWH0000007	Set free cooling
VMWH0300000	Sensors on
VMWH0300002	Sensors off
VMWH0100010	LED panel on
VMWH0100000	LED panel off
VMWH0417744	Reset filter

License

MIT License