Your boiler's internal control board is getting too hot, usually because it is located too close to a heat source or there is a fault with the electronics.

Electronic temperature error could be overheating due to external influences

What causes this fault?

This fault occurs when the boiler’s main electronic control board exceeds its safe operating temperature. It is usually caused by either an internal electrical component failing and generating excess heat, or the control box being exposed to high temperatures from nearby pipes or internal leaks. To prevent permanent damage to the electronics, the boiler shuts down as a safety precaution.