BoilerFaultCodesTechnical description
Occurs five times per second. Cleared by removing fault and/or main switch off/on.
What causes this fault?
This fault occurs when the boiler's internal computer experiences a communication error or fails to complete its safety checking sequence during startup. The most common reason is an electronic glitch within the main control board or a failure in the ignition process that prevents the burner from firing safely. It effectively means the boiler has reached a 'deadlock' where it requires a manual intervention to confirm the system is safe to try again.
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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