BoilerFaultCodesYour boiler's computer brain has been replaced or reset and needs to be told which specific model it is controlling before it can start working.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: Contact Installer
What causes this fault?
This fault occurs when a newly installed circuit board has not been configured to recognize the specific power output of your boiler. Because the same spare part is used across multiple models, the boiler remains in a safety mode until it is told exactly which version it is operating. This usually happens immediately after a repair or if the internal memory has been corrupted by a power surge.
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 Spare PCB Not Set — 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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