BoilerFaultCodesYour boiler has lost connection with its internal temperature sensor, meaning it cannot monitor heat levels and has shut down as a safety precaution.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: NTC Faults
What causes this fault?
This fault occurs when the boiler's main control board loses communication with the temperature sensor that monitors the water leaving the unit. The most common reason is that the sensor itself has failed due to age or internal wear, though it can also be caused by loose wiring or water damage to the electrical connections inside the casing.
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 F.00 — no call-out fees, no surprises.
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