BoilerFaultCodesYour boiler has suffered a major electrical failure where the internal fuse blows instantly, meaning the main control board has likely short-circuited and stopped working.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: fuse blow immediately / Replace electronic board
What causes this fault?
This fault occurs when a component inside the boiler fails and draws too much electricity, causing the internal fuse to blow instantly to protect the system. The most common reason is a short circuit within the main control board itself or a failed internal pump that has suffered an electrical surge.
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.
Gas Safe Register →Protect yourself from future repair bills
A boiler cover plan would cover faults like 1F — no call-out fees, no surprises.
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Parts for discontinued models can be hard to find and expensive. A new A-rated boiler could save you money on both repairs and energy bills.
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