BoilerFaultCodesGlow-worm d.10 Fault Code
Also written as D10 — same fault.
The Glow-worm d.10 fault code means: your boiler is struggling to circulate water properly because the internal pump that moves heat around your radiators is not working as expected.. It appears on 11 Glow-worm models in our database.
Technical description: Statusoftheinternalpumpintheheatingcircuit
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 d.10 fault code
Click a model for the full fault code list and model-specific repair notes.
- Compact Repair: £150-300
- Easicom 24 Repair: £150-300
- Easicom 28 Repair: £150-300
- Energy7 Combi Repair: £180-350
- Flexicom 24c / 28c Repair: £150-350
- MicraCom
- Sustain 12s Repair: £150-350
- Sustain 15s Repair: £150-350
- Sustain 18s Repair: £150-350
- Ultimate 3 25R Repair: £180-350
- Ultimate3 Combi Repair: £250-450
Source
Glow-worm d.10 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 31 August 2026