BoilerFaultCodesYour boiler has stopped working because it cannot detect a signal from the internal sensor that monitors the temperature of your hot water.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: S2 sensor open circuit
What causes this fault?
This fault occurs when the boiler's control board loses communication with the sensor responsible for monitoring your hot water temperature. The most common cause is the sensor itself failing internally, but it can also be triggered by a loose connection or damaged wiring between the sensor and the main circuit board.
Engineer required
This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
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A boiler cover plan would cover faults like F04 — 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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