Sonoff ZigBee Temperature Humidity Sensor SNZB-02P

Sonoff SNZB-02P – Zigbee Temperature & Humidity Sensor

A small battery-powered sensor that monitors room temperature and humidity and sends the readings to your phone. Place it on a shelf, table, or wall mount – it runs for ages on a coin battery, with no wires.

The trick: it uses Zigbee (not Wi-Fi), so it needs a Sonoff Zigbee Bridge Pro to talk to your network. The upside of Zigbee is reliability and battery life – sensors run for months, and the connection stays strong even when your Wi-Fi is wobbly.

Why people buy it

• Get notified when your room is too hot, cold, dry, or humid. Set comfort limits in the app – phone alerts the moment you cross them.
• Automate based on temperature. Trigger a fan to turn on when temp > 30°C, or an AC scene at certain thresholds. Pair with Sonoff smart switches.
• Track climate history. See how your room has felt over the past week, month – useful for spotting humidity problems, finding the best times of day, etc.
• One sensor per room. Place them everywhere – kids’ bedrooms, baby’s room, server closet, wine fridge area – all in the app, all monitored from one phone.

Key Features

• Swiss-made sensor – ±0.2°C temperature accuracy, ±2% humidity accuracy. High precision.
• Updates every 5 seconds when you’re actively viewing.
• Battery-powered (CR2477 coin cell, included) – months of runtime.
• Wireless and tiny – place anywhere with double-sided tape or magnetic mount.
• Historical data in the eWeLink app – view by hour, day, or month.
• Use in automations – trigger lights, switches, or scenes based on temperature or humidity readings.
• Voice control via Google Assistant and Alexa (through the bridge).

💡 Pro Tip: Place one in your baby’s room with alerts set to notify you if temperature drops below 18°C or rises above 26°C. You’ll know the moment the room needs adjusting – without checking your phone every hour.

⭐ Frequently Asked Questions

Does it work on its own?

No – it’s a Zigbee sensor and needs a Sonoff Zigbee Bridge Pro to connect to your network. The bridge bridges Zigbee to Wi-Fi, so your phone (over the internet) can read the sensor.

Can I use one bridge for multiple sensors?

Yes – one Sonoff Zigbee Bridge Pro supports up to 128 sensors. Buy as many SNZB-02P sensors as you need; they all pair to the same bridge.

What’s the battery life?

Several months on the CR2477 coin cell that ships with it. When it runs low, the app will warn you – easy to swap in a fresh battery.

Can I use it outdoors?

No – designed for indoor use only. The casing isn’t weatherproof. For outdoor temperature, look at the waterproof Sonoff WTS01 probe.

Can I view temperature from outside Lebanon?

Yes – as long as the bridge is on and connected to your home Wi-Fi, you can view sensor readings from your phone anywhere in the world via 4G or another Wi-Fi.

The sensor keeps going offline. What’s wrong?

Usually it’s a range issue. Move the Zigbee Bridge Pro closer to the sensor, or higher (better signal coverage). Walls and metal objects interfere with Zigbee – if your sensor is far from the bridge, add a Zigbee smart plug between them as a repeater.

One sensor is offline even though it’s in the same room as another working sensor – why?

Likely a connection issue with the bridge. Try unpairing and re-pairing the offline sensor through the eWeLink app, or check for low battery.

Can it directly turn on a fan when humidity is high?

Not directly – the sensor reports data, it doesn’t switch things on. To automate based on humidity: set up an automation in the eWeLink app that triggers a Sonoff smart switch (S60 plug, MINIR4, MINI Dry) when humidity crosses your threshold. The switch then turns the fan on or off.