Neon B Flashing very slowly Low

Alpha Neon B Flashing very slowly Fault Code

Also written as NEONBFLASHINGVERYSLOWLY — same fault.

The Alpha Neon B Flashing very slowly fault code means: your boiler is currently stuck in a standby or waiting mode because it is receiving power but has not been triggered to start heating.. It appears on 5 Alpha models in our database.

Monitor it

This is a minor fault. Keep an eye on it and mention it at your next annual boiler service. Reset the boiler and see if it clears.

Technical description: Electricity supply to the boiler is on.

DIY fix possible

Check your room thermostat or smart controller settings to ensure they are calling for heatIncrease the temperature setting on your thermostat to see if the boiler fires upCheck if the boiler's own internal hot water or heating dials are turned up sufficiently

Find a Gas Safe engineer

Search the official register for a qualified engineer in your area.

Gas Safe Register →

Alpha models that show the Neon B Flashing very slowly fault code

Click a model for the full fault code list and model-specific repair notes.

Source

Alpha Neon B Flashing very slowly fault code information on this page is sourced and cross-checked against the official Alpha service / installation manuals for each affected model.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed 27 April 2026