BoilerFaultCodesYour boiler has stopped working because its internal temperature sensor cannot send information to the main control board.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: S1 sensor open circuit
What causes this fault?
This fault occurs when the boiler's main control board loses its electrical connection with the primary temperature sensor. This is usually caused by the internal sensor failing completely or a loose connection in the wiring harness that prevents data from being transmitted. Without this temperature reading, the boiler 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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