BoilerFaultCodesYour boiler has detected that a temperature sensor has become loose or disconnected, preventing it from reading how hot the water is.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: Central heating NTC unclipped (Heating flow)
What causes this fault?
This fault occurs when the temperature sensor responsible for monitoring the water leaving the boiler physically detaches from the pipe or loses its electrical connection. This is often caused by a weakened retaining clip that has popped off, or vibrations over time that have loosened the wiring plug connected to the sensor.
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 F19 — no call-out fees, no surprises.
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