BoilerFaultCodesYour boiler's computer memory is blank or incorrect, meaning it doesn't currently know how to operate itself.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: PCB Programming - Unprogrammed state
What causes this fault?
This fault occurs when the boiler's main control board loses its identity and can no longer remember which specific model it is installed in. The most common reason is a electronic failure within the PCB itself or a loose Customer ID chip, which acts like a small memory stick that tells the boiler how to function safely.
Engineer required
This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
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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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