BoilerFaultCodesYour boiler is struggling to provide hot water because its internal temperature sensor has stopped sending a reliable signal.
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: Domestic hot water (DHW) sensor error – sensor damaged, wiring shorted or disconnected
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 become loose or damaged over time. Because the boiler no longer knows how hot the water is, it stops heating it as a safety precaution to prevent scalding.
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 F11 — no call-out fees, no surprises.
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