Build a Basic Arduino Uno-Based Smart Thermostat

Introduction

This project focuses on building a simple smart thermostat using Arduino Uno. The thermostat will allow you to monitor the temperature of a room and control a heating or cooling device based on the temperature readings. This project provides an introduction to temperature sensing and control using Arduino.

The Arduino Uno is an ideal platform for this project due to its versatility and ease of use. We will use a temperature sensor to measure the room temperature and control a relay to activate a heating or cooling device. This project demonstrates fundamental concepts of temperature control and automation.

Let’s go through the materials required and the steps to build your smart thermostat.

Materials

	Arduino Uno Buy at Amazon
	Relay Module Buy at Amazon
	Breadboard Buy at Amazon
	Jumper Wires Buy at Amazon

Instructions

1. Connect the DHT11 sensor to the Arduino:
   • VCC of sensor to 5V on Arduino
   • GND of sensor to GND on Arduino
   • Data pin of sensor to digital pin 2 on Arduino
2. Connect the relay module to the Arduino:
   • VCC of relay module to 5V on Arduino
   • GND of relay module to GND on Arduino
   • IN1 pin of relay module to digital pin 7 on Arduino
3. Connect the heating or cooling device to the relay module according to the relay module’s specifications.
4. Open the Arduino IDE on your computer.
5. Write the following code in the Arduino IDE and upload it to your Arduino board.

#include <"DHT.h">

DHT dht(2, DHT11);

const int relayPin = 7;

void setup() {

dht.begin();

pinMode(relayPin, OUTPUT);

Serial.begin(9600);

}

void loop() {

float temperature = dht.readTemperature();

if (isnan(temperature)) {

Serial.println("Failed to read from DHT sensor!");

return;

}

Serial.print("Temperature: ");

Serial.print(temperature);

Serial.println(" °C");

if (temperature < 22) {  // Set your desired temperature threshold
digitalWrite(relayPin, HIGH);
Serial.println("Heating ON");
}
else 
{
digitalWrite(relayPin, LOW);
Serial.println("Heating OFF");
}
delay(2000);
}

Explanation

The code provided reads the temperature from the DHT11 sensor and controls a relay based on the temperature reading. If the temperature is below a certain threshold (22°C in this case), the relay is activated, turning on the heating device. If the temperature is above the threshold, the relay is deactivated, turning off the heating device.

This project is a basic example of temperature control with Arduino, demonstrating how to use sensors and relays for automation. You can adjust the temperature threshold to suit your needs and expand the project by adding features such as a display or remote control.

Conclusion

Building a smart thermostat with Arduino Uno is a valuable project that teaches you about temperature control and automation. By following this tutorial, you’ve created a system that can help manage room temperature efficiently.

Feel free to modify and expand this project to fit your needs. You can integrate additional sensors, controls, and features to make your smart thermostat even more versatile and useful.

Thank you for following this tutorial. We hope you enjoyed building your smart thermostat and found it educational. Stay tuned for more Arduino projects and tutorials!