BoilerFaultCodesYour boiler has likely experienced an internal electrical fault or a component failure that has caused a safety fuse on the main control board to blow.
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). Before using the fault finding chart ensure all wiring is correct and in good condition, the pump is not faulty and check the PCB fuse F2.
What causes this fault?
This fault occurs when an electrical surge or a component failure causes a safety fuse on the main control board to blow, cutting power to prevent further damage. The most common reason is a seizing water pump that is drawing too much current or a short-circuit within the boiler's internal wiring. As a result, the boiler shuts down completely to protect its sensitive electronic parts.
This fault is more common in the autumn when heating systems are turned on for the first time after summer, as pumps are more likely to seize after long periods of inactivity.
Engineer required
This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
Find a Gas Safe engineer
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A boiler cover plan would cover faults like F2 — no call-out fees, no surprises.
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