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.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed

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

From this model's manual
Verified against the Alpha Intec S installation & service manual, page 27.
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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