click sound on acceleration from tentioner pulley and its effect

i have ford escape hybrid 2009 ,it produce click sound when i turn on AC unit they told this is normal,but i noticed same click from same place (accessory belt tensiner pulley ) when i accelerate every time is this normal ,do i need new tensioner pulley and serpentine or only pulley.if i didnt change wat is its effect on car.thanxa alotfor your help