BoilerFaultCodes.com
01 High

Your boiler has failed to light, which means you will not have any heating or hot water until the issue is resolved.

Technical description: Boiler failed to ignite – problem with gas valve operation, fan failing to start, ignition control board and cables
Typical repair cost: £150-380 (including labour)

Engineer required

This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.

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Protect yourself from future repair bills

A boiler cover plan would cover faults like 01 — no call-out fees, no surprises.

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