Medium
d0 on Alpha Intec S

Your boiler is displaying a code that is not defined in the manufacturer's system, which often indicates a software glitch or a communication error between its internal controls.

Book a service

This fault should be looked at by a Gas Safe engineer within the next week or two. It may get worse if left.

What the manual says

Manufacturer manual

Not used

Shared across the Alpha InTec range
This code is shared by the boilers in this range, which use the same control board. It may not be printed in this exact variant’s manual.
Plain-English guidance below. Severity, DIY steps, costs and parts are our interpretation to help you act, not text from the manual.

Engineer required

This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.

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Related fault codes

All 34 fault codes on the Intec S

Seeing a different code? Every code this model can display, in one place.

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