Shelly temperature + humidity sensors — shelly_rpc setup guide

Local-only integration with Shelly Gen2 / Gen3 H&T sensors over MQTT. No cloud roundtrip. The sensors publish to your Otonomo box's local mosquitto, the driver subscribes, the dashboard updates.

Tested against Shelly H&T Gen3 (battery-powered, ~30–45 min publish cadence).

Prerequisites

1. One or more Shelly H&T Gen3 sensors. ~€25 each on shelly.com or Amazon. The Plus / Pro range with plugged power works too; battery sensors are most common.
2. Sensors paired to your WiFi via the Shelly app.
3. MQTT pointed at your Otonomo box. In the Shelly app:
4. Open the device → Settings → MQTT
5. Enable MQTT
6. Server: <your-otonomo-box-ip>:1883
7. Client ID: leave default (Shelly auto-generates from MAC)
8. MQTT prefix: leave as the device ID (e.g. shellyhtg3-a1b2c3)
9. Save and wait 30 seconds for the device to reconnect.

Otonomo's local mosquitto listens on :1883 with anonymous access enabled on the loopback + LAN interface — no auth needed.

Verifying the sensor is publishing

From any machine on your LAN:

mosquitto_sub -h <otonomo-box-ip> -t 'shelly+/+' -v

Within ~5 minutes (battery wake cycle) you should see lines like:

shellyhtg3-a1b2c3/status/temperature:0  {"id":0,"tC":21.4,"tF":70.5}
shellyhtg3-a1b2c3/status/humidity:0     {"id":0,"rh":47.5}

If nothing appears: the sensor isn't pointing at your box, or it's asleep. Press the sensor's button once to wake it; the next status publish goes out within 2 seconds.

Configuring the driver

1. Local UI → /drivers → shelly_rpc under "Temperature Sensor" → Install.
2. Add instance:

1. Create instance.

Add one driver instance per Shelly. The cards on the local UI's overview page show each sensor independently.

Verifying it landed

• Local UI → main page should show a temperature card for your sensor with the latest reading + age in seconds/minutes.
• A reading age >60 minutes means the sensor is sleeping between cycles — expected behaviour. If it's >2 hours, check the battery.

Common pitfalls

"no data after 30 minutes"

Battery-powered Shelly H&T publishes only on: - Wake interrupt (button press, big temp change) - Scheduled wake (default: every 30–45 min) - Boot

If it's been more than 45 min and nothing arrived, the sensor lost its WiFi or your broker IP changed. Open the Shelly app → device page → there's a connectivity timestamp. If it's stale, hit "Refresh"; the sensor wakes and reconnects.

Multiple sensors, only one shows up

You added multiple shelly_rpc driver instances but only one's device_id is correct. Check the actual device_id strings via mosquitto_sub (see verification section above) and update the remaining instances' configs at /drivers.

Cache file permissions

The cache_file is written by the otonomo system user. If you change the path to a directory it can't write to, the driver still works but loses readings across broker reconnects (no big deal — the sensor publishes again within the next wake cycle).

Sensor placement tips

For best results, especially if you'll pair the readings with the heating orchestrator:

1. Place in occupied rooms, not stairwells or hallways. Average indoor air, not transit air.
2. At waist height, away from direct sun and radiators. Wall between sensor and a window minimizes solar drift.
3. Battery side facing down if mounted vertically — keeps any condensation away from the contacts.

For multi-room targeting, one sensor per heating zone is the typical arrangement. The cloud orchestrator preferentially uses the sensor nearest the room's thermostat target.

What Otonomo will do with this driver

Observe mode: visualize the room temperature + humidity on the overview + per-device pages.

Active mode, when paired with a heat-pump (daikin_local, panasonic_aquarea, vaillant_ebus) and the appropriate capability opt-in: - Adjusts heat-pump / boiler setpoint to drive the room to target, not the indoor unit's intake temperature - Detects open-window-or-door events from a sudden temperature drop and pauses heating until the room recovers - Uses humidity to nudge the dehumidifier control if you also have one

References

• Shelly Gen3 MQTT API: https://shelly-api-docs.shelly.cloud/gen2/General/MqttIntroduction
• Otonomo driver source — otonomo_drivers/drivers/shelly_rpc/

Independent interoperability tool. Not affiliated with Allterco Robotics (the maker of Shelly).