BoilerFaultCodesYour boiler's internal computer brain hasn't been set up with the correct identity settings, so it doesn't know how to operate correctly.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: Temporary error – no input of parameters C1/C2. Printed circuit board (PCB) not configured.
What causes this fault?
This fault occurs when the boiler's main control board has lost its specific identity settings or has recently been replaced without being programmed. It physically prevents the boiler from firing because the system doesn't know which model size or fan speed settings to apply, essentially leaving the appliance in a 'blank' factory state. This is usually caused by a memory failure on the circuit board or a missing configuration plug.
Engineer required
This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
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A boiler cover plan would cover faults like H.02 – .02 — 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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