BoilerFaultCodesYour boiler has lost power to its internal electronics, likely caused by a safety fuse blowing or an electrical fault inside 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: Fuse Type (F1A)
What causes this fault?
This fault occurs when the boiler's internal electrical protection system detects an overload or a short circuit, causing a safety fuse to blow. The most common reason is an electrical component, such as the pump or a valve, failing and drawing too much current, which cuts power to the control board to prevent further damage.
Engineer required
This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
Find a Gas Safe engineer
Search the official register for a qualified engineer in your area.
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A boiler cover plan would cover faults like F1 — no call-out fees, no surprises.
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