Zigbee temperature sensors for Home Assistant: SNZB-02D, Aqara and others

Also available in French.

A Zigbee temperature sensor in each heated room lets you automate heating, spot dry air and get freeze alerts. This guide compares five common Zigbee 3.0 models for Home Assistant—no fixed prices; check retailers when you buy.

Comparison table

Model	Measures	Display	Accuracy (maker)	Battery (maker)	Cell	Best for
SONOFF SNZB-02D	Temp, humidity	LCD	±0.2 °C, ±2 % RH	~2 years	CR2450	Top pick—display, accuracy, battery
Aqara T1 (WSDCGQ11LM)	Temp, humidity, pressure	E-ink	±0.3 °C, ±3 % RH	1–2 years	CR2032	Compact, pressure trend
SONOFF SNZB-02P	Temp, humidity	None	±0.4 °C, ±4 % RH	~1.5 years	CR2477	Budget, no display
Tuya TS0201	Temp, humidity	None	±0.5 °C, ±5 % RH	~1 year	2× AAA	Cheapest, AAA cells
Aqara FP2 (mmWave)	Temp, humidity, presence	None	±0.5 °C (secondary)	Mains USB-C	—	Presence first, temp bonus

SONOFF SNZB-02D — our pick

• LCD shows temp and humidity without opening the app
• Best claimed accuracy in this list
• CR2450 often lasts ~2 years
• Min/max last 24 h on display
• Works with ZHA and Zigbee2MQTT

Example links: Amazon UK · Amazon US · 2-pack UK

How many sensors?

• Studio: 1
• ~50 m² flat: 2 (living + bedroom)
• ~80 m²: 3
• ~120 m² house: 4–5 (skip hall, WC, cupboards)

One per heated or monitored room is enough—you do not need one in every closet.

Placement

Good: centre of room, 1.2–1.8 m height, away from direct sun.
Avoid: above radiators, in front of open windows, inside steamy bathrooms (condensation on the sensor).

Range: ~10–15 m indoors through a couple of walls—add mains Zigbee routers (smart plugs) if farther: smart plugs and Zigbee dongle.

Pair with ZHA

1. Home Assistant → Zigbee (ZHA) → Add device
2. Pull battery tab on SNZB-02D
3. Hold button 5 s until LED blinks
4. Rename and assign area

Entities: temperature, humidity, battery %.

Useful automations

Heat below 19 °C (daytime only):

automation:
  - alias: "Living room heat below 19C"
    trigger:
      - platform: numeric_state
        entity_id: sensor.living_room_temperature
        below: 19
    condition:
      - condition: time
        after: "06:00"
        before: "22:00"
    action:
      - service: switch.turn_on
        target:
          entity_id: switch.radiator_plug_living_room

Nursery alert outside 17–24 °C and humidity above 70 % for an hour follow the same pattern with notify.mobile_app.

Troubleshooting

• Won’t pair: fresh battery, within 3 m of coordinator, 10 s reset if needed.
• Wrong reading: move away from sun or radiator; calibrate with a template sensor if consistently ~1 °C off.
• Humidity stuck at 99 %: dry the sensor; avoid permanent install in very wet rooms.

Zigbee vs DIY ESP32

Zigbee: coin cell, no cable, months–years on battery. ESP32 + ESPHome: USB power, cheaper parts, fully custom—ESPHome temperature guide.

Also: Zigbee2MQTT vs ZHA · PIR lighting on Raspberry Pi.

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