homebridge-mnet

Homebridge plugin that bridges Mitsubishi Electric M-NET centralized AC controllers (G-50A / GB-50A / G-50 / G-50B / G-50BA) to Apple HomeKit. Each indoor unit appears as a HomeKit HeaterCooler accessory.

Built on top of the g50a-client library — auto-discovers indoor units from the controller, no manual address mapping needed.

Install

Through the Homebridge UI: search homebridge-mnet and click Install. Or via npm:

sudo npm install -g homebridge-mnet

Configure

Minimal config — just the controller's IP:

{
  "platforms": [
    {
      "platform": "MNET",
      "name": "M-NET",
      "host": "192.168.1.1"
    }
  ]
}

Full config schema (all fields beyond host are optional):

| Field | Default | Notes | |---|---|---| | host | — | Required. IP or hostname of your G-50A controller. | | port | 80 | Almost never needs changing. | | pollIntervalMs | 5000 | How often to read state from the controller. Range 2000–60000. | | autoModeDeadbandC | 2.0 | HomeKit's AUTO mode wants two thresholds; the controller has one setpoint. We bracket the setpoint by ±half this value. | | groupNames | {} | Per-group display-name overrides keyed by group number string. | | excludeGroups | [] | Group numbers to hide from HomeKit. |

The Homebridge UI surfaces all of this through a form — no need to edit JSON by hand.

What gets exposed

For each registered indoor unit on the controller, a HeaterCooler accessory with:

• Active — on/off
• CurrentHeaterCoolerState — Inactive / Idle / Heating / Cooling, derived from the live mode and the room-vs-setpoint delta
• TargetHeaterCoolerState — Auto / Heat / Cool
• CurrentTemperature — room (inlet) temperature
• CoolingThresholdTemperature / HeatingThresholdTemperature — setpoints, with min/max pulled from the controller's reported CoolMin/CoolMax/HeatMin/HeatMax
• RotationSpeed — fan speed, bucketed (Low / Mid1 / Mid2 / High) per the unit's reported capability
• SwingMode — Swing / Auto louver
• StatusFault — flips to general fault if the indoor unit reports ErrorSign or the controller becomes unreachable

Migration from v1

The v1 plugin required a hand-written mnet_config.json with KNX-style 1/3/2 sub-addresses for every characteristic. v2 throws all of that away — set host and optionally groupNames, the rest is auto-discovered. There is no automated migration tool; just re-enter your room names in the UI.

Requirements

• Node 22.10+ (or 24+)
• Homebridge 1.8+ (works on 2.x)
• A G-50A / GB-50A / similar controller reachable over HTTP on your LAN. The plugin does not require any controller-side configuration beyond the indoor units being registered as groups.

Security

The XML protocol on these controllers is unauthenticated on the wire — the applet's "login" only gates the UI. Anyone on the LAN can reconfigure the controller. Treat your controller as needing network segmentation; do not expose it to the internet.

See docs/g50a-protocol.md §6 for the disassembly evidence behind this claim.

Troubleshooting

• "No host configured" — set host in the platform config.
• "Controller unreachable" — verify ping works to the controller and HTTP responds: curl http://<host>/index.html returns HTML.
• Group missing in HomeKit — restart Homebridge once after first install. The plugin auto-discovers but waits for the controller's group-list refresh (10 min) before unpublishing missing groups, which can confuse first-run timing.
• Group Model="??" — appears for the first 1–2 minutes after registering new units on the controller. The plugin filters these out until they resolve to Model="IC". Restart Homebridge or wait.

License

ISC.