BoilerFaultCodesWhat the manual says
Manufacturer manualPCB Programming - Off state
From this model's manual
Verified against the Zanussi Ultra Combi installation & service manual.
What causes this fault?
This fault occurs when the boiler's internal computer has been set to a software-off state, often following a power cut or a manual adjustment in the programming menu. Instead of a mechanical breakdown, the boiler has essentially 'forgotten' it should be running and is stuck in a standby mode. In some cases, this can also happen if the main circuit board has a glitch and requires a professional reconfiguration.
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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