What does the Glow-worm Ultimate F75 fault code mean?
The F75 fault code on the Glow-worm Ultimate boiler indicates a domestic hot water (DHW) electrical error, which typically points to a malfunction in the DHW sensor or wiring issues. This error can prevent the boiler from providing hot water, affecting overall performance.
Common Causes
- DHW Sensor Failure: The DHW temperature sensor may be faulty or damaged, leading to incorrect readings and triggering the fault code.
- Wiring Issues: Damaged or loose wiring connections related to the DHW system can cause electrical faults, resulting in the F75 error.
Can I fix it myself? (DIY)
It is recommended to call a Gas Safe Engineer for this issue, as it involves electrical components that can be dangerous to handle without proper training. Attempting to fix it yourself could lead to further damage or safety hazards.
Estimated Repair Cost (2026 UK Prices)
The estimated repair cost for resolving the F75 fault code is around £150 to £250, depending on whether the DHW sensor needs replacing or if wiring repairs are required. This cost reflects the price of parts and the labour involved in diagnosing and fixing the issue.