2 Pack MQ‑2 Combustible Gas & Smoke Sensor Module

LPG, Methane, Hydrogen & Smoke Detection

Versatile MQ‑2 combustible gas and smoke sensor module for detecting LPG, methane, hydrogen, alcohol, and smoke, perfect for DIY leak alarms, safety monitors, and smart‑home ventilation projects.

MQ‑2 Combustible Gas & Smoke Sensor Module Compatibility 

Works with Arduino, ESP32, ESP8266, Raspberry Pi, STM32, and most 5V‑powered microcontroller platforms using the analog output and optional digital threshold output.

Key Features 

Detects a wide range of combustible gases and fumes including LPG, propane, butane, methane, hydrogen, alcohol, carbon monoxide, and smoke, making it suitable for general leak and smoke detection.

Metal‑oxide (SnO₂) sensing element whose resistance drops as gas concentration increases, providing an analog signal correlated to gas levels.

Breakout module integrates the MQ‑2 sensor, comparator circuit, and trim potentiometer, exposing both analog (AO) and digital (DO) outputs for flexible use.

High sensitivity and fast response over a typical detection range of roughly 200–10,000 ppm for many target gases, depending on calibration.

Onboard power and signal LEDs make it easy to verify sensor power and digital alarm output at a glance.

Technical Specs

Sensor type: MQ‑2 metal‑oxide semiconductor (MOS) gas sensor.

Operating voltage: typically 5 V DC on standard modules (some support 2.5–5 V).

Detection gases: LPG, propane, butane, methane, hydrogen, alcohol, carbon monoxide, and smoke.

Typical concentration range: about 200–10,000 ppm for combustible gases (exact ranges vary by gas and calibration).

Heater voltage: around 5.0 V ± 0.2 V to maintain sensor operating temperature.

Outputs: analog voltage proportional to gas concentration (AO) and digital TTL output (DO) with adjustable trigger threshold via onboard potentiometer.

Module size: typically around 32 × 20 to 40 × 21 mm, with 4‑pin header (VCC, GND, AO, DO).

Preheat time: requires several seconds for basic operation, and up to 24 hours initial burn‑in for stable calibrated measurements.

Ideal Uses

DIY gas leak alarms for LPG and natural gas around stoves, heaters, and gas lines (non‑certified, hobby use).

Smoke and fumes detection in workshops, garages, and maker spaces to trigger fans or alerts.

Smart‑home and IoT projects that monitor air for combustible gases and send notifications or control ventilation.

Educational projects exploring gas‑sensing principles, analog signal processing, and calibration with microcontrollers.

What’s Included

2 × MQ‑2 Combustible Gas & Smoke Sensor Module.

Safety Note

The MQ‑2 is intended for hobby and educational gas‑detection projects and is not a certified safety device. Do not rely on this module as the only protection against gas leaks or fire; always follow local safety codes and use approved detectors for life‑critical applications.