This project is a Temperature Controller System built using an Arduino, DHT11 temperature sensor, and a motor (or fan) driver module. The system continuously monitors the surrounding temperature using the DHT11 sensor and automatically changes the fan speed and heater On/OFF on preset temperature conditions to keep the room temperature normal.
This project is a Temperature Controller System built using an Arduino, DHT11 temperature sensor, and a motor (or fan) driver module.
It continuously monitors the ambient temperature and automatically controls a heater (LED) and fan speed based on the temperature range.
The system also displays real-time temperature and humidity on an LCD screen.
- Real-time temperature and humidity monitoring using DHT11 sensor
- Automatic fan speed control (Low / Medium / High)
- Heater (LED) turns ON when temperature falls below 27°C
- LCD display for live temperature and humidity readings
- Simple, cost-effective, and easy to build project
- The DHT11 sensor measures the surrounding temperature and humidity.
- The Arduino reads this data and checks the temperature range.
- Based on the temperature, the system automatically controls the heater (LED) and fan speed using the motor driver.
| Temperature Range | Action | Description |
|---|---|---|
| Below 27°C | Heater (LED) ON | Indicates heating mode (cold condition) |
| 27°C – 29°C | Fan ON (Low Speed) | Mild cooling |
| 30°C – 32°C | Fan ON (Medium Speed) | Moderate cooling |
| Above 32°C | Fan ON (High Speed) | Maximum cooling |
- The LCD display continuously shows real-time temperature and humidity readings.
| Component | Quantity | Description |
|---|---|---|
| Arduino Uno Rev3 | 1 | Microcontroller board |
| DHT11 Sensor | 1 | Temperature and humidity sensor |
| L293D Motor Driver | 1 | Motor driver IC or module |
| DC Motor / Fan | 1 | Output fan |
| 16x2 I2C LCD | 1 | Display module |
| LED + Resistor | 1 | Used as heater indicator |
| Jumper Wires | - | For connections |
| Breadboard | 1 | Prototype setup |
Make sure you have the following libraries installed in your Arduino IDE:
#include <Adafruit_Sensor.h>
#include <DHT.h>
#include <DHT_U.h>
#include <Wire.h>
#include <LiquidCrystal_I2C.h>