BoilerFaultCodesYour boiler has stopped working because it cannot correctly monitor the temperature of the water leaving the unit.
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 S1 defective
What causes this fault?
This fault occurs when the boiler's control board loses communication with the sensor responsible for measuring the heat of the water leaving the unit. The most common reason is that the internal components of the sensor have failed due to age or electrical wear, though it can also be caused by loose or damaged wiring connecting the sensor to the main board.
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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