A02.55 Medium

Remeha A02.55 Fault Code

Also written as A0255 — same fault.

The Remeha A02.55 fault code means: your boiler's computer memory has lost or cannot recognise its unique identification number, which prevents it from starting up correctly.. It appears on 1 Remeha model in our database.

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.

Technical description: Inval or miss SerNR
Typical repair cost £150-300 (including labour)

Engineer required

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

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Remeha models that show the A02.55 fault code

Click a model for the full fault code list and model-specific repair notes.

Source

Remeha A02.55 fault code information on this page is sourced and cross-checked against the official Remeha service / installation manuals for each affected model.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed 7 July 2026