High
neon illuminated on Alpha 240E / 280E

Your boiler has developed an internal electrical fault, meaning the control board is likely failing and unable to safely operate the system.

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

1. Replace neon PCB. 2. check PCB-M11 connector. 3. 20V DC across terminals 49, 52. 4. Replace main PCB.

Shared across the 240E / 280E range
This code is shared by the boilers in this range, which use the same control board. It may not be printed in this exact variant’s 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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All 8 fault codes on the 240E / 280E

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

Burner output modulatesFan runs at max. speedPrimary flow switch operatedPump circulating water / NoPump runsRed reset button illuminatedSpark at ignition electrodes

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