I’ve tried the DHT11 sensor modules at both Vcc 3.3V and 5.0V, and at both voltages the humidity values are bad. dfrobot has introduced a V2 DHT11 sensor module that changes the 10K pull-up to 4.7K.

The project is equipped with a DHT11 sensor to read the room's temperature and an LCD to display this temperature reading and the speed the motor is currently ... an Arduino Uno, a 16x2 LCD, ...