BoilerFaultCodesYour boiler has lost power to its main control board because an internal fuse has blown, meaning the unit cannot function at all.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: Fuse (F1A) on Printed Circuit Board
What causes this fault?
This fault occurs when an electrical surge or a faulty component causes the internal safety fuse on the control board to blow. The most common reason is a short circuit in a part like the fan or pump, which draws too much power and breaks the circuit to protect the boiler from further damage.
This fault is slightly more common in winter when the boiler's electrical components, such as the pump and fan, are under the most constant strain.
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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