BoilerFaultCodesYour boiler's main control board has suffered an internal electronic failure and is unable to manage the heating process safely.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: Main PCB fault
What causes this fault?
This fault occurs when the boiler’s central brain experiences an internal electrical failure, preventing it from safely controlling the gas flow and ignition. The most common reason is a component failure on the circuit board itself, though sometimes a faulty gas valve can send an incorrect signal that triggers this specific error.
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 F62 — 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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