Temperature based Fan Speed Controller

                                        ARDUINO CODE
#include <DHT.h>
#include <LiquidCrystal.h>
LiquidCrystal lcd(12,11,5,4,3,2);
float temp;
DHT dht(7,DHT22);
#define fan 9
void setup() {
// giving fan current ...... Making fan pin 9 for output:
 pinMode(fan,OUTPUT);
 //Setting LCD's number of rows and column:
 lcd.begin(16,3);
 //printing message on the LCD
 lcd.setCursor(3,1);
 lcd.print("Project");
 delay(1000);
 lcd.clear();
 dht.begin();
 }

void loop() {
 if(analogRead(A0)>10)
 {
 lcd.setCursor(3,0);
 lcd.print("Recording");
 lcd.setCursor(2,1);
 lcd.print("Temperature...");
 delay(3000);
 lcd.clear();
 lcd.setCursor(0,2);
 temp=dht.readTemperature();
 lcd.setCursor(5,1);
 lcd.print(temp);
 lcd.print(" C");
 delay(3000);
 lcd.clear();
  if(temp<20)
  {
    analogWrite(9,0);
     lcd.setCursor(1,1);
    lcd.print("Fan Off");
    delay(2000);
    lcd.clear();
  }
    else if(temp>20 && temp<=24)
  {
    analogWrite(fan, 51);
     lcd.setCursor(1,1);
    lcd.print("Fan Speed: 20%");
    delay(2000);
    lcd.clear();
  }
  else if(temp>=24 && temp<=26)
  {
    analogWrite(fan, 102);
    lcd.setCursor(1,1);
    lcd.print("Fan Speed: 40%");
    delay(2000);
    lcd.clear();
  }
  else if(temp>=26 && temp<=28)
  {
    analogWrite(fan, 153);
     lcd.setCursor(1,1);
    lcd.print("Fan Speed: 60%");
    delay(2000);
    lcd.clear();
  }  
  else if(temp>=28 && temp<=30)
  {
    analogWrite(fan, 200);
     lcd.setCursor(1,1);
    lcd.print("Fan Speed: 80%");
    delay(2000);
    lcd.clear();
  }  
  else if(temp>=30)
  {
    analogWrite(fan, 255);
     lcd.setCursor(1,1);
    lcd.print("Fan Speed: 100%");
    delay(2000);
    lcd.clear();
  }  
 }
 else{
   lcd.setCursor(1,1);
    lcd.print("No one sitting");
     analogWrite(9,0);
    delay(3000);
  }
}