Low
A4 on Sime Metropolis DGT 25 BF

Your boiler is displaying a memory code indicating that it previously encountered a fault and shut down for safety reasons, though it may currently be working.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed

Monitor it

This is a minor fault. Keep an eye on it and mention it at your next annual boiler service. Reset the boiler and see if it clears.

What the manual says

Manufacturer manual

Code of last error -4

From this model's manual
Verified against the Sime Metropolis Dgt 25 Bf installation & service manual, page 19.
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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A01View →A02View →A03View →

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