BoilerFaultCodesWhat the manual says
Manufacturer manualInternal boiler control error
From this model's manual
Verified against the Potterton Powermax He installation & service manual.
What causes this fault?
This fault occurs when the boiler's main control board suffers a hardware failure and can no longer communicate with the internal sensors. It is usually caused by electrical components on the circuit board wearing out over time or a loose connection in the internal wiring loom. Because the 'brain' of the boiler can no longer monitor safety, it shuts the entire system down as a precaution.
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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