BoilerFaultCodesYour boiler has detected a problem with its internal temperature sensor, which means it cannot accurately monitor the water heat and has stopped working 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: Sensor 5 fault
What causes this fault?
This fault occurs when the boiler's internal control board loses communication with the temperature sensor or receives an illogical reading. The most common reason is that the sensor's electrical resistance has moved out of range due to age, or the wiring connecting the sensor to the main board has become loose or damaged.
Engineer required
This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
Find a Gas Safe engineer
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A boiler cover plan would cover faults like F012 — 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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