Should the letter 'A' appear in the display it is possible that the bulb is faulty. Switch on the light and if it does not come on then simply replace the bulb. Bulbs for your hood can be purchased from the spares section on our website.
If the lamp lights up try and switch the hood off at the mains supply for a few minutes. Restore the power and try again. Should the fault persist then please ring us for further advice.