BoilerFaultCodesYour boiler has detected an issue with a temperature sensor that is preventing it from heating your home or water safely.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: Sensor fault S5.
What causes this fault?
This fault occurs when the boiler's internal control system loses communication with the S5 temperature sensor or receives an incorrect reading. The most common reason is a physical failure of the sensor's internal components or a loose connection in the wiring harness that links the sensor to the main control board.
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 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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