BoilerFaultCodesTechnical description
Installation in unfinished state - Fault during boiler venting
What causes this fault?
This fault occurs during the commissioning stage when the boiler's internal computer determines that air is still trapped within the heat exchanger or primary circuit. It is often triggered because the automatic venting program was interrupted or the system's air bleed valve is stuck, preventing the unit from safely transitioning into normal operation. No gas will be ignited until the boiler is satisfied that all air has been purged to prevent overheating.
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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