Gas oven fails to ignite, display shows F20 after several ignition attempts.

Safety: Turn off gas supply and disconnect power before working on gas components. If you smell gas continuously, ventilate the area and contact a gas professional immediately.

• Check gas supply: Ensure the gas shut-off valve to the Ariston range is open and that other gas appliances work.
• Inspect igniter: Locate the oven burner and spark electrode. Clean the electrode tip with a soft brush to remove carbon or grease. Ensure the ceramic insulator is not cracked.
• Check spark: With the oven reassembled and power restored, start an oven ignition cycle and observe through the viewing holes. You should see a strong blue spark at the electrode. If not, the electrode or ignition module may be faulty.
• Replace igniter: Disconnect power and gas again. Remove the mounting screw(s) holding the electrode, disconnect the wire, and install a new Ariston oven igniter electrode.
• Ignition module: If there is no spark on any burner, the ignition module may be defective and should be replaced by a qualified technician.