Unknown
A on Main Combi 24

Main Combi 24 fault code A

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed

What the manual says

Manufacturer manual

The flue or flue terminal is blocked or obstructed in some way, or there is an internal fault.

From this model's manual
Verified against the Main/Main Combi 24 4747402 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.

Engineer required

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

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All 10 fault codes on the Combi 24

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

2A3A170WBCDEG20IPX4D

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