BoilerFaultCodesTechnical description
Final fault code (Refer to section 7.11)
What causes this fault?
This fault occurs when the boiler tries to light the flame several times but fails to detect one, causing it to shut down for safety. The most common reasons include a blocked gas supply, worn-out spark electrodes that can no longer ignite the gas, or a faulty internal component failing to open the gas valve.
This fault is more common during the first cold snap of winter, when increased demand can highlight underlying issues with the ignition components or external gas supply.
Engineer required
This is a high severity fault. Stop using the boiler and call a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
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