Frequently asked questions

• How do I choose between AirGuard PM2.5 and AirGuard CO2?

  By symptom: stuffiness, drowsiness and fogged-up windows point to CO2 — take the SAWF-08P. Street dust, stove smoke, allergies or renovation point to particles — take this SAWF-07P. They measure different things and do not replace each other.
• Which particle sensor is inside — is it laser-based?

  Sonoff does not officially publish the sensor model or type. The official specification states a 0–500 µg/m³ range and ±10% (0–100 µg/m³) / ±10 µg/m³ (100–500 µg/m³) accuracy — those are the numbers to rely on.
• Why can't it be wall-mounted?

  The back of the case carries the air-intake vents; flat against a wall the airflow is blocked and readings lose accuracy — the warning comes from the manufacturer itself. Use the fold-out stand on a desk or shelf.
• Does it work with Apple Home and Siri?

  Yes: via Matter it joins Apple Home and works with Siri, iPhone, iPad and Apple Watch. Sonoff's official note: to see humidity in Apple Home, the iPhone must run iOS 26 or later.
• Do I need a hub to use it?

  Not for eWeLink — the device connects straight to 2.4 GHz Wi-Fi. A Matter hub (HomePod, Nest Hub, Echo and the like) is only needed to add it to third-party ecosystems: Apple Home, Google Home, Alexa or SmartThings.
• What is in the box and what power do I need?

  The monitor, a USB-A to Type-C cable and a quick guide. There is no wall adapter in the package — Sonoff states this right on the official box-contents image; any 5V/1A USB-A charger will do.
• What do the indicator colours mean and when does the alarm sound?

  Green — up to 35 µg/m³, yellow — 36–53, red — from 54 upward. During an alarm the buzzer can be muted with a button: the unit goes quiet for 30 minutes while the LED and push alerts keep working. A full Do Not Disturb mode is there too.
• Can I adjust the readings or switch PM2.5 to PM10?

  Yes, in the on-device menu: a short press of the settings button opens a mode where temperature and humidity are calibrated, the °C/°F unit is changed and the PM2.5/PM10 display is toggled. A 10-second long press restores factory settings.