BoilerFaultCodesYour boiler's internal computer has detected a problem with how it manages the flame, causing it to shut down for safety.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: Internal control unit error
What causes this fault?
This fault occurs when the boiler's electronic brain becomes confused or receives conflicting signals from the sensors that monitor the burner's flame. It typically happens because the main control board has developed an internal electrical flaw or can no longer accurately verify that the gas has ignited safely.
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 E35 — no call-out fees, no surprises.
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