High
uP on Zanussi Ultra Plus Combi

Your boiler is currently stuck in its startup or programming sequence and is not yet ready to provide heat or hot water.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed

Call an engineer soon

Book a Gas Safe engineer within 24 to 48 hours. Your boiler may be unsafe or could break down completely if left.

What the manual says

Manufacturer manual

PCB Power up / Programming Mode

From this model's manual
Verified against the Zanussi Ultra Plus Combi installation & service manual.
Plain-English guidance below. Severity, DIY steps, costs and parts are our interpretation to help you act, not text from the manual.

What causes this fault?

This fault occurs when the boiler's main internal computer loses its configuration or gets stuck during its initial boot sequence. The most common reason is a power surge or a failing printed circuit board that can no longer hold its basic programming instructions.

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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