BoilerFaultCodesYour boiler has experienced a fundamental electronic control failure that has caused it to lock 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: EK lockout failure – this is a permanent error
What causes this fault?
This fault occurs when the boiler's internal computer, or 'brain', suffers a critical hardware failure that prevents it from managing safety functions. It is typically caused by a component failure on the printed circuit board or a communication breakdown between the electronic control box and the rest of the system. Because the boiler can no longer guarantee safe operation, it will stop working immediately and cannot be overridden.
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 E1-71 — 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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