High
AL 08 on Sime Metropolis DGT 25 BF

Your boiler is failing to detect a flame, which means it cannot fire up to provide heating or hot water.

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

Fault in the flame detection circuit — check ignition electrode; verify gas supply/pressure

From this model's manual
Verified against the Sime Metropolis Dgt 25 Bf 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 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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