Oven emits high‑pitched buzzing or humming noise from control area

Safety first: Disconnect power before touching any internal electrical components.

• Identify source: With the oven running (qualified persons only), carefully listen to locate the noise (transformer, relay, or fan). Then disconnect power and access that area.
• Tighten mounts: Ensure the control board and any small transformers are firmly screwed down. Add insulating washers if necessary to reduce vibration.
• Check relays: A chattering relay may indicate low voltage or a failing coil. If a relay is excessively noisy, replace the main control board or have the relay replaced professionally.
• Acceptable hum: A slight hum is normal; only address if it is unusually loud or accompanied by malfunction.