BoilerFaultCodesYour boiler has lost track of the temperature of the water flowing through it because an internal sensor is broken.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: Flow sensor defective.
What causes this fault?
This fault occurs when the internal sensor responsible for monitoring the heat of the water leaving the boiler fails or sends an impossible reading to the control board. The most common reason is the sensor's electrical resistance drifting out of range due to age, though it can also be triggered by a loose connection or damaged wiring. Because the boiler no longer knows how hot the water is, it shuts down as a safety precaution to prevent overheating.
Engineer required
This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
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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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