BoilerFaultCodesYour boiler's internal computer brain has developed a memory error and can no longer process the information it needs to run safely.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: EEPROM error | Electronics defective
What causes this fault?
This fault occurs when the main control board suffers a permanent memory failure, meaning it can no longer remember the specific settings required to run your boiler safely. The most common reason is a physical hardware defect within the internal circuitry, often caused by age or an electrical surge that has damaged the board’s microchips.
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 F.63 — no call-out fees, no surprises.
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Could it be time for a new boiler?
If repair costs are adding up, a new energy-efficient boiler could be the smarter long-term choice.
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