what is wron how can I mend it?

I have a white knight cl8487,it goes but even with only a few items in it is takeing ages to dry its like it isnt heating up,you can have it on for an hour and nothing is even warm,it can take a whole day to dry a few items so it dos eventually dry,I bought it second hand and so dont even have a manual,do you also know where I can get one