BoilerFaultCodesWhat the manual says
Manufacturer manualDefective 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 internal computer chips suffer a hardware failure or a communication breakdown between the electrical components. The most common reason is natural wear and tear of the delicate electronic circuits over time, or damage caused by an unexpected electrical power surge.
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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