No, they wont charge (or rather they should not charge). As per warranty agreement, a manufacturer can first try to repair the phone. if his attempt is unsuccessful, the customer has every right to ask for a replacement.
This is generally what is followed in the service industry (myself being in one of them). To know the exact condition, you should refer your warranty card.
@ohjhani - if it has happened to you twice, you can always ask for a replacement.