BoilerFaultCodesYour boiler has detected an electrical fault with the internal sensor that monitors the temperature of the water used for your heating, 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: Flow temperature sensor short circuit
What causes this fault?
This fault occurs when the boiler's internal computer receives an electrical signal suggesting the temperature sensor has malfunctioned or 'short-circuited'. The most common reason is that the sensor itself has failed internally, but it can also be caused by water leaking onto the electrical connections or a damaged wire touching the boiler's metal casing.
Engineer required
This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
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A boiler cover plan would cover faults like F.11 — no call-out fees, no surprises.
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Could it be time for a new boiler?
If repair costs are adding up, a new energy-efficient boiler could be the smarter long-term choice.
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