100FF Low

Glow-worm 100FF Fault Code

The Glow-worm 100FF fault code means: the code you are seeing is not a fault; it is simply a technical specification label on your boiler indicating its maximum heating power output.. It appears on 1 Glow-worm model 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: NOMINAL kW HEAT INPUT(NETT) Min. 26.44 Med. 29.24 Max. 32.38

Engineer required

This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.

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Glow-worm models that show the 100FF fault code

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

Source

Glow-worm 100FF 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 7 July 2026