High Lockout
F13 on Ferroli Modena HE

Your boiler's internal temperature sensor has stopped sending the correct information to the control board, preventing the system from operating safely.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed

Call an engineer soon

Book a Gas Safe engineer within 24 to 48 hours. Your boiler may be unsafe or could break down completely if left.

Technical description

Exchanger probe error – t-sensor damaged, short circuited, sensor damaged or wiring broken

What causes this fault?

This fault occurs when the sensor responsible for monitoring the heat exchanger's temperature fails to communicate with the main control board. The most common reason is that the sensor has physically degraded or developed a short circuit, meaning the boiler can no longer verify if it is operating at a safe temperature. In some cases, the error is caused by loose or damaged wiring connecting the sensor to the brain of the boiler.

Engineer required

This is a high severity fault. Stop using the boiler and call a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.

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Related fault codes

F10View →F11View →F14View →

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