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A boiler fault code alone is not a gas or carbon-monoxide emergency. If you smell gas, a CO alarm sounds, or someone has possible carbon-monoxide symptoms, leave and call 0800 111 999 from outside.

Safe check: The user guide instructs you to rotate all control knobs fully clockwise, turn the boiler power off and on, then press restart. If you are unsure, stop and contact an engineer.

Gas Safe registered engineer: The fault remains or returns after the user guide action; contact Ideal if the boiler is under warranty or arrange a Gas Safe registered engineer.