High
H21-052 on Ideal Mini C28

Your boiler has detected that one of its outer side casing panels is not fitted correctly or is loose, which prevents the boiler from operating safely.

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.

Technical description

Side case panel

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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