Glow-worm F.65 Fault Code
Also written as F65 — same fault.
The Glow-worm F.65 fault code means: your boiler's control system has detected that its internal electronic components are overheating, so it has shut down to protect itself from damage.. It appears on 17 Glow-worm models in our database.
Technical description: Fault: Electronics temperature too high
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 →Avoid the next call-out bill
A cover plan would handle faults like F.65: no call-out fees, no surprise bills.
Affiliate links. We may earn a commission at no extra cost to you.
Glow-worm models that show the F.65 fault code
Click a model for the full fault code list and model-specific repair notes.
- Betacom4 Repair: £150-300
- Compact Repair: £200-400
- Easicom3 Combi Repair: £150-350
- Easicom3 System Repair: £250-450
- Energy Repair: £150-300
- Energy Regular Repair: £150-300
- Energy System Repair: £150-300
- Energy7 Combi Repair: £150-300
- Energy7 Regular Repair: £150-300
- Energy7 System Repair: £150-300
- Essential Repair: £150-300
- Flexicom 24c / 28c Repair: £180-350
- MicraCom Repair: £200-400
- Sustain 12s Repair: £180-350
- Ultimate 3 25R Repair: £150-350
- Ultimate3 Combi Repair: £150-300
- Ultimate3 System Repair: £180-350
Source
Glow-worm F.65 fault code information on this page is sourced and cross-checked against the official Glow-worm service / installation manuals for each affected model.
- Glow-worm Betacom4 manual (PDF)
- Glow-worm Compact manual (PDF)
- Glow-worm Easicom3 Combi manual (PDF)
Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed 7 July 2026