High
F.28 on Vaillant ecoTEC plus Aquaplus

Your boiler has failed to ignite and has shut itself down as a safety precaution because it cannot detect a flame.

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

Boiler goes to lock out | No gas; Insufficient gas; Incorrect gas valve adjustment; Electrode defective; Ignition lead defect; Electronic igniter defective

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.29View →

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