At the very bottom, on the front of the oven, left hand side is a small panel. Its held with an allen key bolt. Unscrew this and pull the battery holder out. It takes a 1.5 volt AA size.
Pete, January 2010
Mine was doing the same. Had to buy a new "Spark Generator". The model number you need is an M250GG.
You can find various places on the net selling them for between £59 and £64.
Hope this helps!
