BoilerFaultCodesYour boiler has detected a fault with the sensor that monitors exhaust fumes, causing the system to shut down for safety.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: Flue gas probe short-circuited
What causes this fault?
This fault occurs when the internal sensor responsible for monitoring the temperature of exhaust gases identifies an electrical short-circuit. The most common reason is that moisture or heat stress has damaged the sensor's internal wiring, causing it to send an incorrect signal to the main control board. As a result, the boiler shuts down immediately to prevent potential damage to the flue system or the heat exchanger.
Engineer required
This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
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