BoilerFaultCodesYour boiler's main internal computer has encountered a processing error and cannot safely operate.
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 fault
What causes this fault?
This fault occurs when the boiler's main control board experiences a critical electronic failure, meaning it can no longer communicate with the internal sensors or components. The most common reason is a component failure on the circuitry itself, often caused by age, a power surge, or moisture ingress affecting the delicate electronics.
This fault is slightly more common during the winter months when heating systems are under constant load and electrical components are more susceptible to failing under continuous thermal stress.
DIY fix possible
Press the reset button on the control panel onceTurn the main power switch to the boiler off, wait 30 seconds, and turn it back onEnsure the boiler has not been subject to a recent power surge or lightning strike
Find a Gas Safe engineer
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A boiler cover plan would cover faults like E01 — 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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