High
F28 on Heatline CaprizPlus 24a

Your boiler has tried to light several times but cannot establish a steady flame, which means your heating and hot water will not work.

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.

What the manual says

Manufacturer manual

Burner fails to ignite, initially, this may be due to air in the gas supply line.

From this model's manual
Verified against the Heatline Caprizplus 24a installation & service manual, page 30.
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 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

F29View →F27View →F54View →

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