no power at all

You do not have any voltage to the unit? Did you check for voltage at the outlet? If your not getting any power at the outlet then there is a electrical issue with in the circuit of the house. You will need to have that looked at by an electrician, or plug the unit into an outlet that is good. If you do have power but the nothing is working on the unit, the fuse is probably bad inside the unit. This fuse is usually on the filter board located behind the control panel at the top. I have attached a video that shows this. AT about 3:40 in the video.