MQ4 Gas Leak Detector
Sensors · Board: ESP32 · Day 8 of 100
An MQ-4 sensor on the ESP32 watches for methane and sounds a buzzer when levels spike. Practical safety project with analog threshold alarms.
How it works
The MQ-4's sensing element changes resistance in the presence of methane, which the ESP32 reads as a shifting analog voltage. Once that voltage crosses a calibrated danger threshold, the board sounds the buzzer. The sensor needs a warm-up period before its readings stabilize.
What you'll learn
- Gas sensor warm-up behavior
- Analog alarm thresholds
- Sensor calibration basics
- Safety system design
Full project: code, wiring diagram & Wokwi simulation
The complete build guide lives in the original repo. Ours is a summary — the real thing is one click away.
Open full project on GitHub ↗Summary by SkillShop. Project by Kritish Mohapatra — code and diagrams belong to the original repo.
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