High
F28 on Glow-worm Ultracom 2 30cxi

Your boiler has stopped working because it cannot successfully start up its flame to heat your home.

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

If the burner fails to ignite "F28" will be displayed, initially, this may be due to air in the gas supply line.

From this model's manual
Verified against the Glow Worm/Glow Worm Ultracom2 24cxi installation & service manual.
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 →F75View →

All 33 fault codes on the Ultracom 2 30cxi

Seeing a different code? Every code this model can display, in one place.

ErrF00F01F10F11F20F22F23F24F26F27F29F32F49F61F62F63F64F65F67F68F70F71F72F73F74F76F77F83F84F85F86

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