Gas cooktop shows F20 or a flashing gas symbol and shuts off gas shortly after ignition.

Safety: Turn off gas and disconnect power. Work in a ventilated area and avoid sparks or flames.

• Observe flame: Light the burner and watch whether the flame properly envelops the thermocouple tip. If the flame is small or off-center, clean the burner cap and ports.
• Clean burner: Remove the burner cap and head. Clean all gas ports with a soft brush and ensure correct reassembly.
• Check thermocouple position: The thermocouple tip should sit in the outer part of the flame. Gently adjust its position if bent away.
• Inspect connections: Under the cooktop, trace the thermocouple lead to the gas valve. Tighten the nut connection carefully; do not overtighten.
• Replace thermocouple: If the burner still goes out and F20 appears, replace the Hotpoint-Ariston thermocouple for that burner. If multiple burners are affected, the safety gas valve or control module may be faulty and require professional replacement.