Medium Lockout
F13 on Intergas Rapid 25

Your boiler's hot water sensor has failed or become disconnected, meaning the system cannot tell how hot your water is and has stopped heating it for safety.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed

Book a service

This fault should be looked at by a Gas Safe engineer within the next week or two. It may get worse if left.

Technical description

DHW sensor open circuit

What causes this fault?

This fault occurs when the boiler's control board loses communication with the sensor responsible for monitoring your hot water temperature. The most common reason is that the internal component has suffered an electrical failure or the connecting wires have vibrated loose or become damaged over time.

Engineer required

This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.

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Related fault codes

F10View →F11View →F12View →F15View →

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