Everyone prefers to work in a cool and comfortable environment, free from excessive heat. However, manually turning a cooling fan on and off based on the temperature can be inconvenient and time-consuming. This is why an automated temperature-controlled cooling system is highly beneficial.
- Monitoring the amount of temperature inside the room.
- Turn on and off automatically the cooling fan depending on the level of temperature inside the room.
- MPK kit
- Relay module
- DHT11 Sensor
- 12V Cooling fan
- 12V Voltage supply
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Figure: Components used to make connection on the board
Figure: DHT11 sensor and relay connection
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#includeDHT.h>
#define FAN_PIN 6 // The Arduino Nano pin connected to relay which drives the fan
#define DHT_PIN 8 // The Arduino Nano pin connected to DHT11 sensor
#define DHT_TYPE DHT11
const int THRESHOLD_ON = 30; // upper threshold of temperature, change to your desire value
const int THRESHOLD_ON = 28; // upper threshold of temperature, change to your desire value
DHTdht(DHT_PIN, DHT_TYPE);
float temperature; // temperature in Celsius
voidsetup() {
Serial.begin(9600); // Initialize the Serial to communicate with the Serial Monitor.
dhtbegin(); // initialize the sensor
pinMode(FAN_PIN, OUTPUT); // initialize digital pin as an output
}
voidloop(){
// wait a few seconds between measurements.
delay(2000);
temperature = dhtreadTemperature();; // read temperature in Celsius
if(isnan(temperature)) {
Serial.println(“Failed to read from DHT sensor!”);
}else{
if(temperature > THRESHOLD_ON){
Serial.println(“The fan is turned on”);
digitalWrite(FAN_PIN, HIGH); // turn on
}else if(temperature < THRESHOLD_OFF){
Serial.println(“The fan is turned off”);
digitalWrite(FAN_PIN, LOW); // turn on
}
}
}
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const int THRESHOLD_ON = 25; // upper threshold of temperature, change to your desire value (temperature to turn fan on)
const int THRESHOLD_OFF = 20; // lower threshold of temperature, change to your desire value (temperature to turn fan off)
