Creating hysteresis with DHT11 sensor..

Using Arduino Project Guidance
6

OK try again... still only reads in 1 deg c increments

void loop()
{

  float h = dht.readHumidity();
  float t = dht.readTemperature();
  // check if returns are valid, if they are NaN (not a number) then something went wrong!
  if (isnan(t) || isnan(h)) {
    Serial.println("Failed to read from DHT");
  } 
  else {
    Serial.print("Humidity: "); 
    Serial.print(h);
    Serial.print("  %   ");
    Serial.print("Temp: "); 
    Serial.print(t);
    Serial.println("C");
  }


  // set the cursor to column 0, line 1
  // (note: line 1 is the second row, since counting begins with 0):
  lcd.setCursor(8, 1);
  lcd.print("H:");
  lcd.print(h);
  lcd.print("%");
  //delay(2000);
  lcd.setCursor(0, 1);
  lcd.print("T:");
  lcd.print(t);
  //lcd.print("C");
  //delay(2000);


  if(t>=27)

  { 
    digitalWrite(fan, HIGH);
    lcd.setCursor(15, 0);
    lcd.print("F");
  }

  if(t<=25)

  { 
    digitalWrite(fan, LOW);
    lcd.setCursor(15, 0);
    lcd.print("_");
  }