BoilerFaultCodesYour boiler's internal computer has encountered a critical communication error and cannot process commands to heat your home.
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 central brain, the Printed Circuit Board, can no longer send or receive signals correctly throughout the system. The most common reason is a physical failure of the electronic components on the board or a loose connection in the wiring harness that links the controls together.
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 E41 — no call-out fees, no surprises.
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