BoilerFaultCodesGlow-worm NEON2 Fault Code
The Glow-worm NEON2 fault code means: your boiler is receiving a request to turn on the heating or hot water, but it has not yet successfully fired the burner.. It appears on 12 Glow-worm models in our database.
Technical description: DEMAND ON
What causes the Glow-worm NEON2 fault?
This fault occurs when the boiler recognizes you want heating or hot water but fails to complete its internal safety checks to ignite the flame. It is usually caused by a mechanical failure in the fan or the air pressure switch, which prevents the boiler from proving it can safely expel exhaust gases. As a result, the system stays in a 'holding' pattern and refuses to fire the burner for safety reasons.
This issue often surfaces during the first cold spell of autumn when a fan that has sat idle all summer struggles to spin up to the required speed.
Engineer required
This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
Find a Gas Safe engineer
Search the official register for a qualified engineer in your area.
Gas Safe Register →Glow-worm models that show the NEON2 fault code
Click a model for the full fault code list and model-specific repair notes.
- Fuelsaver Complheat 40 55 Repair: £95-260
- Hideaway 100
- Hideaway 40B
- Hideaway 80
- Micron 30ff Repair: £120-350
- Micron 40FF Repair: £120-350
- Micron 50FF Repair: £120-350
- Micron 60FF Repair: £120-350
- Space Saver Repair: £90-180
- Space Saver 30 40 50 Repair: £90-180
- Ultimate Repair: £100-280
- Ultimate3 Repair: £100-280
Source
Glow-worm NEON2 fault code information on this page is sourced and cross-checked against the official Glow-worm service / installation manuals for each affected model.
Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed 27 April 2026