Hotpoint CTD00 Leaking Masses Of Water?

Hi, hoping someone can help. My Hotpoint CTD00 tumble dryer started leaking water at the back yesterday and the plastic "water holder" at the top is no longer filling up. We have taken the back off and have no idea where the leak is coming from. The dryer still works. Any help would be much appreciated, it is only 2 years old and I'd hate to have to get rid of it! Thanks!