Medium
AL 83 on Sime Mia 30

Your boiler has detected that the gas is not burning correctly, which may cause it to turn off temporarily for safety.

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

Irregular combustion (temporary error)

From this model's manual
Verified against the Sime Mia 30 installation & service manual, page 45.
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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