BoilerFaultCodesWhat the manual says
Manufacturer manualImproper electrical connection of gas control combination or defective control panel.
From this model's manual
Verified against the Ideal Maximiser Se installation & service manual.
What causes this fault?
This fault occurs when the boiler's main computer loses the ability to talk to the gas valve, which is the component that controls fuel flow. The most common reason is an electrical glitch in the circuit board or a loose connection in the wiring that prevents these two parts from synchronising safely.
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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