BoilerFaultCodesGlow-worm d.36 Fault Code
Also written as D36 — same fault.
The Glow-worm d.36 fault code means: your boiler is struggling to detect or regulate the flow of water needed to provide your hot taps, often because the system is sensing an issue with the water moving through it.. It appears on 11 Glow-worm models in our database.
Technical description: Value for the domestic hot water flow rate
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 d.36: 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 d.36 fault code
Click a model for the full fault code list and model-specific repair notes.
- Compact Repair: £120-250
- Easicom 24 Repair: £150-250
- Easicom 28 Repair: £150-250
- Energy7 Combi Repair: £150-250
- Flexicom 24c / 28c Repair: £150-250
- MicraCom Repair: £120-250
- Sustain 12s Repair: £120-250
- Sustain 15s Repair: £120-250
- Sustain 18s Repair: £120-250
- Ultimate 3 25R Repair: £150-250
- Ultimate3 Combi Repair: £150-250
Source
Glow-worm d.36 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