Low
D.22 on Vaillant Turbomax Plus 828 E

Your boiler is currently performing an internal background system check and is not actually reporting a hardware malfunction.

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.

Technical description

Diagnostic code check (page 53) / Internal control status

Engineer required

This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.

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