BoilerFaultCodesTechnical description
Safety lockout. To reset the boiler, turn the left knob on position (reset) position, wait one minute to cool down the boiler, and then turn it on previous operating position.
What causes this fault?
This fault occurs when the boiler's internal sensors detect an unsafe operating condition, such as the water getting too hot or the burner failing to light correctly. As a protective measure, the system 'locks out' to prevent any damage to the internal components or your property. The most common reasons include a buildup of air in the system, a blockage in the pipework, or a failure in the ignition process.
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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