BoilerFaultCodesTechnical description
The flame is extinguished too late after the gas valve closes
What causes this fault?
This fault occurs when the boiler's sensors detect a flame for several seconds after the heating cycle has finished and the gas should have stopped flowing. The most common reason is a gas valve that is physically sticking open or an electrical fault in the control board that fails to cut power to the valve. In some cases, a carbon-coated sensing electrode may also be providing a false signal back to the boiler.
Engineer required
This is a emergency severity fault. Stop using the boiler and call a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
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