The STEM Makers

How to Build a Temperature & Humidity Monitor using Arduino

A Temperature & Humidity Monitor using Arduino uses a DHT11 or DHT22 sensor to measure environmental conditions and displays them on an LCD or Serial Monitor. This project is perfect for learning sensor integration and real-time data monitoring, useful for weather stations, greenhouses, and smart home systems. 

 ✅ Main Components Required 

  • Arduino Uno (or compatible board) 
  • DHT11/DHT22 Sensor (for temperature and humidity) 
  • 16×2 LCD Display (or OLED) with I2C module (optional) 
  • Resistors (10kΩ) 
  • Jumper Wires 
  • Breadboard 
  • Power Supply (USB or Battery) 

 ✅ What is a Temperature & Humidity Monitor? 

It is an electronic system that continuously measures the temperature and humidity of the environment using a sensor and displays the readings on an LCD or a serial monitor. It is widely used in weather monitoring, agriculture, and IoT-based applications. 

 ✅ How Does the System Work? 

  • DHT11/DHT22 Sensor measures temperature and humidity using a capacitive humidity sensor and thermistor. 
  • Arduino reads the sensor data and processes it. 
  • Output: The readings are displayed on the Serial Monitor or LCD screen in real time. 

 ✅ Step-by-Step Setup Guide 

  1. Connect the DHT Sensor:
    VCC → 5V
    GND → GND
    Data → Arduino Digital Pin 2 
  2. Connect the LCD (Optional):
    Use I2C for easy wiring or connect via standard pins. 
  3. Install Libraries:
    Install DHT sensor library and LiquidCrystal_I2C (if using LCD) from Arduino IDE Library Manager. 
  4. Upload the Code:
    Open Arduino IDE, write the code, and upload it. 
  5. Test:
    View readings on the Serial Monitor or LCD. 

 ✅ Sample Arduino Code 

#include “DHT.h”
#define DHTPIN 2
#define DHTTYPE DHT11   // Change to DHT22 if using that sensor

DHT dht(DHTPIN, DHTTYPE);

void setup() {
  Serial.begin(9600);
  dht.begin();
}

void loop() {
  float humidity = dht.readHumidity();
  float temperature = dht.readTemperature();

  if (isnan(humidity) || isnan(temperature)) {
    Serial.println(“Failed to read from DHT sensor!”);
    return;
  }

  Serial.print(“Temperature: “);
  Serial.print(temperature);
  Serial.print(” °C | Humidity: “);
  Serial.print(humidity);
  Serial.println(” %”);
 
  delay(2000);
}
 (You can add LCD display code for better visualization.) 

 ✅ Advantages of Arduino-Based Temperature & Humidity Monitor 

  • Accurate & Real-Time Monitoring 
  • Low Cost & Easy to Build 
  • Expandable for IoT Applications 
  • Energy Efficient 
  • Beginner-Friendly 

 ✅ Enhancements You Can Add 

  • LCD Display for portable monitoring. 
  • IoT Integration with ESP8266 or NodeMCU for remote data access. 
  • Data Logging to SD Card or Google Sheets. 
  • Buzzer or LED Alerts for high temperature/humidity. 
  • Mobile App Integration via Bluetooth or Wi-Fi. 

 ✅ The STEMMakers Capability in Arduino projects 

At The StemMakers based out of Vijayawada near DV Manor Hotel, we have successfully built 20+ custom Arduino projects for student science exhibitions and IoT learning programs for various science fairs and competitions.
Contact us for kits, training, and expert guidance:
📧 asha@thestemmakers.com | 🌐 www.thestemmakers.com

Discover additional Arduino projects by The STEM Makers through the links below.

Know More about Arduino Consulting at The STEM Makers
How to build a water level indicator Arduino
How to Build a Smart Dustbin using Arduino
How to Build a Smart Home Automation using Arduino
How to Build a Traffic Light System using Arduino
How to Build a Temperature & Humidity Monitor using Arduino
How to build an Obstacle Avoiding Robot using Arduino
How to build an Automatic Plant Watering System using Arduino 

 

 

Scroll to Top