BoilerFaultCodesYour boiler's computer has lost touch with the internal components that control the gas flow, meaning it cannot safely light the burner.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: Loss of communication between gas valve and boiler printed circuit board (PCB) or fault in air/gas unit.
What causes this fault?
This fault occurs when the boiler's main control board can no longer send or receive signals from the gas valve assembly. It is usually caused by a loose connection in the internal wiring or a critical electronic failure within the gas valve itself, which prevents the system from safely managing the fuel flow. Without this constant communication link, the boiler enters a safety mode to ensure no unburned gas enters the system.
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 E.02 – .17 — 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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