No touch hand dryers are fairly advanced pieces of machinery. However, depending on what is wrong with your broken unit, you may be able to repair it yourself. First, check with your manual that came from the manufacturer. There should be some troubleshooting touchless dryer tips that you can go through before worrying about calling them or a repair person.
Take a close look at the situation. Do you smell anything coming from the unit? If you smell anything resembling a smoky or burning smell, chances are you have fried a circuit and will need help with the repair. If no smells are there, your no touch hand dryer probably has something simple wrong.
Go through the troubleshooting tips one by one. If you still have trouble figuring out what went wrong with your unit, contact the manufacturer for their recommendations. If they are no help, get the yellow pages or the web to help you find an electrician who can help.