High
F.12 on Vaillant Combi Compact 282EB

Your boiler has detected a internal blockage that is preventing water from flowing correctly and affecting the system's pressure.

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

A blockage in the appliance is affecting the system’s pressure.

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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Related fault codes

F.00View →F.10View →F.20View →

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