Is This Right for Me?

CO₂ sensor: NDIR, ±(50 ppm + 5%)
CO₂ range: 400–5000 ppm
Refresh rate: Every 5 seconds
Also measures: Temperature (±0.5°C) & Humidity (±3% RH)
Display: 3.73" LCD, °C/°F switchable
Connectivity: Wi-Fi 2.4 GHz (802.11 b/g/n) + Matter
Power: USB-C, 5V / 1A (continuous)
Data history: 365 days, exportable
Dimensions: 70 × 103 × 26 mm, 101 g
Material: PC + ABS

Product Details

Indoor CO₂ climbs fast in a closed room – and you feel it as drowsiness, headaches and poor focus long before you notice the air has gone stale. The Sonoff AirGuard CO2 puts that invisible number on a clear desktop screen, so you always know when it’s time to crack a window or run the fan.

At its core is a professional NDIR sensor accurate to ±(50 ppm + 5%), measuring CO₂ from 400 to 5000 ppm and refreshing the reading every 5 seconds. The large 3.73-inch LCD shows live CO₂ in ppm next to room temperature and humidity at a glance, with switchable °C/°F units – no app needed for a quick check.

When CO₂ rises, AirGuard warns you three ways: an on-device sound alarm, a colour-coded indicator light, and a push notification to your phone. In the eWeLink app it combines your indoor readings with your city’s outdoor air data to suggest the right action, and it keeps a full year of CO₂, temperature and humidity history you can chart and export to spot long-term patterns.

Built on Matter over Wi-Fi, it drops straight into Apple Home, Google Home, Amazon Alexa, SmartThings and Home Assistant, so your air readings sit alongside the rest of your smart home and can trigger automations like switching on a purifier. Ask Siri or your smart speaker for the current level and get an instant, hands-free answer. (Integrating with a third-party Matter ecosystem requires a Matter hub.)

What You Get

See invisible CO₂
Live ppm on a clear LCD tells you when a room has gone stale and needs fresh air.
Professional NDIR accuracy
±(50 ppm + 5%) sensor, 400–5000 ppm range, refreshing every 5 seconds.
Three-way alerts
Sound, light and phone notifications warn you the moment CO₂ climbs too high.
Works with Matter
Apple Home, Google Home, Alexa and SmartThings - all at once, over Wi-Fi.
A full year of history
Store and export 365 days of CO₂, temperature and humidity trends.
Hands-free checks
Ask Siri or your speaker for the current CO₂ level - no app needed.

A Closer Look

Professional NDIR accuracy

An NDIR sensor measures CO₂ from 400–5000 ppm to ±(50 ppm + 5%) and refreshes every 5 seconds.

Professional NDIR accuracy

CO₂, temperature & humidity at a glance

A clear 3.73-inch LCD shows all three readings together, with switchable °C/°F units.

CO₂, temperature & humidity at a glance

Works with the Matter ecosystem

Apple Home, Google Home, Alexa, SmartThings and Home Assistant - over Wi-Fi, no proprietary hub.

Works with the Matter ecosystem

Three-way alerts

Sound alarm, colour-coded indicator light and phone notifications warn you the moment CO₂ gets too high.

Three-way alerts

A full year of air-quality history

Store and export up to 365 days of CO₂, temperature and humidity trends to find the root cause.

A full year of air-quality history

Works With

eWeLink
Works
Apple Home (Matter)
Works
Google Home
Works
Amazon Alexa
Works
SmartThings
Works
Home Assistant
Works
Siri
Works

What's in the Box

1× SONOFF AirGuard CO2 Monitor (SAWF-08P)
1× USB-C power cable
1× User manual

Delivery & Pickup

Standard Delivery
All Lebanon governorates - Greater Beirut usually next day; Tripoli, Jbeil, Saida, Tyre, Zahle, Akkar and the rest within 2–4 working days.
4 $ · Free over 50 $
Express Delivery
Faster shipping - usually within 24 hours of order confirmation (Greater Beirut & Metn). Same-day not guaranteed.
6 $ flat
Pickup - Dekwaneh
Collect from our Dekwaneh store. Weekdays 10am–5pm, Sat 10am–1pm.
3 $ · Free over 30 $

Warranty & Support

6-month Local Warranty
Covers defects in materials & workmanship. Handled here in Lebanon.
WhatsApp Support - Always On
Can't set it up? Message us. We reply within minutes, not days.
14-day Exchange - Unopened Items
The item must be unopened and in its original packaging. Exchange it for a product of equal or higher value - we do not give cash refunds. Opened items are covered by the warranty if there is a factory defect.
Free Setup Call
If you get stuck, we'll walk you through the setup on a free WhatsApp call.

Frequently Asked Questions

Does it need to stay plugged in? ›
Yes - the AirGuard CO2 is continuously powered over USB-C (5V/1A). Constant power is what lets the NDIR sensor refresh the reading every 5 seconds; there is no built-in battery.
Do I need a hub? ›
No for everyday use - it connects directly to your 2.4 GHz Wi-Fi and the eWeLink app. To bring it into a third-party Matter ecosystem (Apple Home, Google Home, Alexa, SmartThings), you'll need a Matter hub for that platform.
Can I mount it on the wall? ›
No. The back of the device has air vents for accurate gas detection, and mounting it flat against a wall can affect the readings. Use it free-standing on a desk or shelf.
How often does the CO₂ reading update? ›
Every 5 seconds, thanks to the professional NDIR sensor and continuous power.
Why does the alarm sound again after I silenced it? ›
Pressing the buzzer once mutes it for 30 minutes to avoid constant disturbance; if CO₂ is still high after that, it sounds again. Press the button again and check the buzzer icon is off on screen to fully disable it, or use Do Not Disturb mode.
Does it measure anything besides CO₂? ›
Yes - it tracks temperature and humidity at the same time, shown together on the LCD, with switchable °C/°F units.

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