BoilerFaultCodesYour boiler has lost power to its main control system because a small internal safety fuse has blown.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: ogress. 24 V fuse blown. Replace fuse. (Incomplete description from text block)
What causes this fault?
This fault occurs when a surge of electricity or a component failure causes the small protective fuse on the main circuit board to blow. The most common reason is a short circuit within an internal part like the pump or fan, or a fault in the low voltage wiring which forces the fuse to pop to protect the expensive control board. Until this fuse is replaced and the underlying short is fixed, the boiler will remain completely unresponsive.
This fault is slightly more common in winter when components like the pump and fan are working at their hardest, increasing the likelihood of an electrical strain that can pop a fuse.
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 P1 — no call-out fees, no surprises.
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