Medium
c3 on Sime Metropolis DGT 25 BF

Your boiler's electronic control system is showing an error because its internal settings have become corrupted or are not properly configured.

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

Number approached the parameters installator

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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Related fault codes

c1View →c2View →c4View →

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