BoilerFaultCodesYour boiler has experienced an internal electronic failure or a communication error between its main control components.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: Permanent fault caused by channel service unit (CSU) time-out or printed circuit board (PCB) damage.
What causes this fault?
This fault occurs when the boiler's internal computer system suffers a critical communication failure or a physical hardware breakdown. It is typically caused by a malfunctioning main circuit board that can no longer send or receive signals correctly, or damaged internal wiring that has interrupted the connection between components. Essentially, the 'brain' of the boiler has stopped working, meaning it can no longer safely control the heating process.
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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Gas Safe Register →Protect yourself from future repair bills
A boiler cover plan would cover faults like E.02 – .16 — 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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