High
ALL 92 on Sime Brava Slim HE System

Your boiler is struggling to get the right balance of air and gas for safe burning and has automatically locked itself out to prevent damage.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed

Call an engineer soon

Book a Gas Safe engineer within 24 to 48 hours. Your boiler may be unsafe or could break down completely if left.

What the manual says

Manufacturer manual

System has reached maximum air correction error (at the minimum flow rate)

From this model's manual
Verified against the Sime Brava Slim He installation & service manual, page 34.
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 is a high severity fault. Stop using the boiler and call a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.

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