BoilerFaultCodesYour boiler has stopped working because an internal temperature sensor has failed and can no longer monitor the heating water.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: Sensor S0 is defective.
What causes this fault?
This fault occurs when the boiler's primary temperature sensor becomes unable to send an accurate electrical signal to the main control board. The most common reason is the internal thermistor failing due to age or heat stress, though it can also be caused by loose or damaged wiring connections inside the unit.
Engineer required
This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
Find a Gas Safe engineer
Search the official register for a qualified engineer in your area.
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A boiler cover plan would cover faults like F000 — 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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