{"product_id":"arduino-co2-monitor-kit-mh-z19-sensor-oled-and-ventilation-alert","title":"Arduino CO2 Monitor Kit: MH-Z19 Sensor, OLED \u0026 Ventilation Alert","description":"\u003ch1\u003eBuild a CO2 Monitor with Arduino Uno \u0026amp; MH-Z19: OLED Display \u0026amp; Ventilation Alert\u003c\/h1\u003e\n\n\u003cp class=\"value-summary\"\u003eEvery part needed, pre-tested for compatibility, with an AI build companion trained on this exact project. Shipped from Bengaluru in 3-5 days.\u003c\/p\u003e\n\n\u003cdiv class=\"specs-strip\"\u003e\n  \u003cspan\u003e\u003cstrong\u003eDifficulty:\u003c\/strong\u003e Intermediate\u003c\/span\u003e\n  \u003cspan\u003e\u003cstrong\u003eBuild Time:\u003c\/strong\u003e 3-4 hrs\u003c\/span\u003e\n  \u003cspan\u003e\u003cstrong\u003eAge:\u003c\/strong\u003e 15-18\u003c\/span\u003e\n  \u003cspan\u003e\u003cstrong\u003eSkill:\u003c\/strong\u003e Environmental Sensing \u0026amp; Threshold Logic\u003c\/span\u003e\n\u003c\/div\u003e\n\n\u003cp\u003eIndoor air quality directly impacts focus, health, and learning-especially in crowded classrooms, labs, and homes across India. This kit puts a professional-grade MH-Z19B NDIR CO? sensor into your hands, letting you build a portable monitor that displays live ppm readings on an OLED screen, switches a traffic-light LED from green to red as levels rise, and screams a buzzer warning the moment CO? crosses 1000ppm. It is the same science behind commercial air quality monitors, now on your breadboard.\u003c\/p\u003e\n\n\u003ch2\u003eWhat You'll Build\u003c\/h2\u003e\n\u003cp\u003eYou'll assemble a compact, battery-powered device that reads CO? concentration every second using the MH-Z19B's non-dispersive infrared sensor. The Arduino Uno processes the data and drives a 0.96-inch OLED showing exact ppm. When CO? is below 800ppm, a green LED glows; 800-1000ppm lights a red LED; above 1000ppm, the buzzer pulses to demand ventilation. The result is a desktop sentinel for dorm rooms, maker spaces, or any enclosed area where stuffiness signals it's time to open a window.\u003c\/p\u003e\n\n\u003ch2\u003eWhat You'll Learn\u003c\/h2\u003e\n\u003cul\u003e\n  \u003cli\u003eInterfacing a digital NDIR gas sensor via UART with Arduino Uno\u003c\/li\u003e\n  \u003cli\u003eReading and calibrating real-time ppm data from the MH-Z19B\u003c\/li\u003e\n  \u003cli\u003eProgramming multi-level threshold logic to control LEDs and a buzzer\u003c\/li\u003e\n  \u003cli\u003eOutputting dynamic sensor data on an I2C OLED display\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003ch2\u003eKit Contents\u003c\/h2\u003e\n\u003ctable\u003e\n  \u003cthead\u003e\u003ctr\u003e\n\u003cth\u003eComponent\u003c\/th\u003e\n\u003cth\u003eQuantity\u003c\/th\u003e\n\u003c\/tr\u003e\u003c\/thead\u003e\n  \u003ctbody\u003e\n    \u003ctr\u003e\n\u003ctd\u003eArduino Uno R3\u003c\/td\u003e\n\u003ctd\u003e1\u003c\/td\u003e\n\u003c\/tr\u003e\n    \u003ctr\u003e\n\u003ctd\u003eMH-Z19B CO2 Sensor\u003c\/td\u003e\n\u003ctd\u003e1\u003c\/td\u003e\n\u003c\/tr\u003e\n    \u003ctr\u003e\n\u003ctd\u003e0.96in OLED\u003c\/td\u003e\n\u003ctd\u003e1\u003c\/td\u003e\n\u003c\/tr\u003e\n    \u003ctr\u003e\n\u003ctd\u003e5mm Red LED\u003c\/td\u003e\n\u003ctd\u003e2\u003c\/td\u003e\n\u003c\/tr\u003e\n    \u003ctr\u003e\n\u003ctd\u003e5mm Green LED\u003c\/td\u003e\n\u003ctd\u003e2\u003c\/td\u003e\n\u003c\/tr\u003e\n    \u003ctr\u003e\n\u003ctd\u003eActive Buzzer\u003c\/td\u003e\n\u003ctd\u003e1\u003c\/td\u003e\n\u003c\/tr\u003e\n    \u003ctr\u003e\n\u003ctd\u003e10k? Resistors\u003c\/td\u003e\n\u003ctd\u003e5\u003c\/td\u003e\n\u003c\/tr\u003e\n    \u003ctr\u003e\n\u003ctd\u003e220? Resistors\u003c\/td\u003e\n\u003ctd\u003e5\u003c\/td\u003e\n\u003c\/tr\u003e\n    \u003ctr\u003e\n\u003ctd\u003e100nF Caps\u003c\/td\u003e\n\u003ctd\u003e5\u003c\/td\u003e\n\u003c\/tr\u003e\n    \u003ctr\u003e\n\u003ctd\u003e400-pt Breadboard\u003c\/td\u003e\n\u003ctd\u003e1\u003c\/td\u003e\n\u003c\/tr\u003e\n    \u003ctr\u003e\n\u003ctd\u003eM-M Wires\u003c\/td\u003e\n\u003ctd\u003e25\u003c\/td\u003e\n\u003c\/tr\u003e\n    \u003ctr\u003e\n\u003ctd\u003e9V Battery Snap\u003c\/td\u003e\n\u003ctd\u003e1\u003c\/td\u003e\n\u003c\/tr\u003e\n  \u003c\/tbody\u003e\n\u003c\/table\u003e\n\n\u003ch2\u003eWhy Buy This Kit Instead of Sourcing Parts Separately\u003c\/h2\u003e\n\u003ctable\u003e\n  \u003cthead\u003e\u003ctr\u003e\n\u003cth\u003eFactor\u003c\/th\u003e\n\u003cth\u003eSourcing Separately\u003c\/th\u003e\n\u003cth\u003eCompoden Kit\u003c\/th\u003e\n\u003c\/tr\u003e\u003c\/thead\u003e\n  \u003ctbody\u003e\n    \u003ctr\u003e\n\u003ctd\u003eCompatibility checks\u003c\/td\u003e\n\u003ctd\u003eYou verify every part\u003c\/td\u003e\n\u003ctd\u003ePre-tested as a system\u003c\/td\u003e\n\u003c\/tr\u003e\n    \u003ctr\u003e\n\u003ctd\u003eBuild support\u003c\/td\u003e\n\u003ctd\u003eForums and scattered tutorials\u003c\/td\u003e\n\u003ctd\u003eAI companion trained on this exact project\u003c\/td\u003e\n\u003c\/tr\u003e\n    \u003ctr\u003e\n\u003ctd\u003eTime to first working build\u003c\/td\u003e\n\u003ctd\u003eDays of debugging\u003c\/td\u003e\n\u003ctd\u003eHours, with step-by-step guidance\u003c\/td\u003e\n\u003c\/tr\u003e\n    \u003ctr\u003e\n\u003ctd\u003eShipping coordination\u003c\/td\u003e\n\u003ctd\u003eMultiple sellers, multiple delays\u003c\/td\u003e\n\u003ctd\u003eOne shipment from Bengaluru in 3-5 days\u003c\/td\u003e\n\u003c\/tr\u003e\n  \u003c\/tbody\u003e\n\u003c\/table\u003e\n\n\u003ch2\u003eWho This Kit Is For\u003c\/h2\u003e\n\u003cp\u003eDesigned for CBSE Class 11-12 students building investigatory projects, B.Tech ECE\/EEE first-years exploring sensor integration, ATL Tinkering Lab mentors seeking a reliable air-quality module, and Smart India Hackathon participants needing rapid prototyping. If you've tinkered with Arduino before and want to move beyond blinking LEDs into real-world environmental sensing, this kit matches your skill level and delivers a permanent learning tool.\u003c\/p\u003e\n\n\u003ch2\u003eBuilt and Backed by Compoden\u003c\/h2\u003e\n\u003cp\u003eEvery Compoden kit ships with an AI build companion trained on this exact project - accessible via a QR code on the box, with WhatsApp and email backup. We've spent 10 years building projects for makers, schools, and institutions across India. If a part fails because of a manufacturing defect, replace it free within 7 days.\u003c\/p\u003e\n\n\u003cdetails\u003e\u003csummary\u003eWhat if I get stuck during the build?\u003c\/summary\u003e\u003cp\u003eScan the QR code on the box to open the AI companion tailored to this kit; it can debug your wiring, explain code, or suggest calibration steps. You can also reach us via WhatsApp for live problem-solving.\u003c\/p\u003e\u003c\/details\u003e\n\u003cdetails\u003e\u003csummary\u003eCan I power the monitor with a USB cable instead of a 9V battery?\u003c\/summary\u003e\u003cp\u003eYes, the Arduino Uno can be powered by its USB port while the sensor and OLED run from its 5V pin. The 9V battery snap is included for portable, standalone use.\u003c\/p\u003e\u003c\/details\u003e\n\u003cdetails\u003e\u003csummary\u003eHow do I calibrate the MH-Z19B sensor?\u003c\/summary\u003e\u003cp\u003eThe sensor auto-calibrates over 24 hours in fresh air, but the AI companion will show you how to trigger a manual fresh-air calibration using a jumper or code command if you need accuracy sooner.\u003c\/p\u003e\u003c\/details\u003e\n\u003cdetails\u003e\u003csummary\u003eWill this project work for a CBSE physics or computer science investigatory?\u003c\/summary\u003e\u003cp\u003eAbsolutely. The kit covers sensor physics, data acquisition, threshold logic, and display programming-exactly the depth CBSE evaluators expect. The AI companion even suggests documentation angles.\u003c\/p\u003e\u003c\/details\u003e\n\n\u003cdiv class=\"kit-description\"\u003e\n  \u003cp\u003eMH-Z19B NDIR CO2 sensor reads ppm level with traffic-light LED and OLED display. Ventilation alert above 1000ppm.\u003c\/p\u003e\n  \u003ch4\u003eWhat's in this kit\u003c\/h4\u003e\n  \u003cul\u003e\n    \u003cli\u003e\u003ca href=\"\/products\/uno-r3-ch340g-atmega328p-board-arduino-compatible\"\u003eArduino Uno R3\u003c\/a\u003e\u003c\/li\u003e\n    \u003cli\u003eMH-Z19B CO2 Sensor\u003c\/li\u003e\n    \u003cli\u003e\u003ca href=\"\/products\/096in-oled-display-128x64-i2cspi-for-arduino-raspberry-pi\"\u003e0.96in OLED\u003c\/a\u003e\u003c\/li\u003e\n    \u003cli\u003e\n\u003ca href=\"\/products\/led-variety-pack-50-pcs-3mm-5mm-mixed-colours\"\u003e5mm Red LED\u003c\/a\u003e x2\u003c\/li\u003e\n    \u003cli\u003e\n\u003ca href=\"\/products\/inductive-proximity-sensor-5mm-npn-no-ceyone-compoden\"\u003e5mm Green LED\u003c\/a\u003e x2\u003c\/li\u003e\n    \u003cli\u003e\u003ca href=\"\/products\/active-buzzer-dc-3-5v-85db-sounder-module-for-arduino-raspberry-pi\"\u003eActive Buzzer\u003c\/a\u003e\u003c\/li\u003e\n    \u003cli\u003e\n\u003ca href=\"\/products\/resistor-variety-pack-100-pcs-10-values-14w-carbon-film\"\u003e10k? Resistors\u003c\/a\u003e x5\u003c\/li\u003e\n    \u003cli\u003e\n\u003ca href=\"\/products\/resistor-variety-pack-100-pcs-10-values-14w-carbon-film\"\u003e220? Resistors\u003c\/a\u003e x5\u003c\/li\u003e\n    \u003cli\u003e\n\u003ca href=\"\/products\/capacitor-variety-pack-6-values-100nf-to-470uf-30-pieces\"\u003e100nF Caps\u003c\/a\u003e x5\u003c\/li\u003e\n    \u003cli\u003e\u003ca href=\"\/products\/breadboard-standard-bundle-830400-tie-points-for-prototyping\"\u003e400-pt Breadboard\u003c\/a\u003e\u003c\/li\u003e\n    \u003cli\u003eM-M Wires x25\u003c\/li\u003e\n    \u003cli\u003e\u003ca href=\"\/products\/9v-battery-snap-connector-with-15cm-wires-compoden\"\u003e9V Battery Snap\u003c\/a\u003e\u003c\/li\u003e\n  \u003c\/ul\u003e\n\u003c\/div\u003e\n\n\u003cscript type=\"application\/ld+json\"\u003e\n{\n  \"@context\": \"https:\/\/schema.org\",\n  \"@type\": \"FAQPage\",\n  \"mainEntity\": [\n    {\n      \"@type\": \"Question\",\n      \"name\": \"What is included in the CO2 Monitor Kit with Arduino Uno + MH-Z19?\",\n      \"acceptedAnswer\": {\n        \"@type\": \"Answer\",\n        \"text\": \"The CO2 Monitor Kit with Arduino Uno + MH-Z19 includes all components needed: Arduino Uno R3, MH-Z19B CO2 Sensor, 0.96in OLED, 5mm Red LED, 5mm Green LED and more. Everything is pre-tested for compatibility and shipped from Bengaluru, India.\"\n      }\n    },\n    {\n      \"@type\": \"Question\",\n      \"name\": \"What skill level is required for the CO2 Monitor Kit with Arduino Uno + MH-Z19?\",\n      \"acceptedAnswer\": {\n        \"@type\": \"Answer\",\n        \"text\": \"This kit is designed for Intermediate level makers, suitable for ages 15-18. MH-Z19B NDIR CO2 sensor reads ppm level with traffic-light LED and OLED display. Ventilation alert above 1000ppm. Estimated build time is 3-4 hrs.\"\n      }\n    },\n    {\n      \"@type\": \"Question\",\n      \"name\": \"Can I buy the CO2 Monitor Kit with Arduino Uno + MH-Z19 online in India?\",\n      \"acceptedAnswer\": {\n        \"@type\": \"Answer\",\n        \"text\": \"Yes, the CO2 Monitor Kit with Arduino Uno + MH-Z19 is available online at Compoden (compoden.in), India's AI-powered electronics and robotics store. Ships from Bengaluru in 1-5 business days across India.\"\n      }\n    }\n  ]\n}\n\u003c\/script\u003e\n\n\u003cscript type=\"application\/ld+json\"\u003e\n{\n  \"@context\": \"https:\/\/schema.org\",\n  \"@type\": \"Product\",\n  \"name\": \"CO2 Monitor Kit with Arduino Uno + MH-Z19\",\n  \"description\": \"MH-Z19B NDIR CO2 sensor reads ppm level with traffic-light LED and OLED display. Ventilation alert above 1000ppm.\",\n  \"sku\": \"CDN-KIT-0115\",\n  \"brand\": {\"@type\": \"Brand\", \"name\": \"Compoden\"},\n  \"offers\": {\n    \"@type\": \"Offer\",\n    \"url\": \"https:\/\/compoden.in\/products\/kit-co2-air-quality-monitor\",\n    \"priceCurrency\": \"INR\",\n    \"price\": \"1540\",\n    \"availability\": \"https:\/\/schema.org\/InStock\",\n    \"seller\": {\"@type\": \"Organization\", \"name\": \"Compoden\"}\n  },\n  \"category\": \"Weather \u0026 Environment\"\n}\n\u003c\/script\u003e","brand":"Compoden","offers":[{"title":"Clone","offer_id":53455299543405,"sku":"CDN-KIT-0115-CL","price":1750.0,"currency_code":"INR","in_stock":true},{"title":"R3 Original","offer_id":53455299576173,"sku":"CDN-KIT-0115-R3","price":4020.0,"currency_code":"INR","in_stock":true},{"title":"R4 WiFi","offer_id":53455299608941,"sku":"CDN-KIT-0115-R4","price":3390.0,"currency_code":"INR","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0999\/3997\/5533\/files\/kit-co2-air-quality-monitor.png?v=1781944247","url":"https:\/\/compoden.com\/products\/arduino-co2-monitor-kit-mh-z19-sensor-oled-and-ventilation-alert","provider":"Compoden","version":"1.0","type":"link"}