What does the Glow-worm Ultimate F45 fault code mean?
The F45 fault code indicates a problem with the domestic hot water (DHW) flow switch in the Glow-worm Ultimate boiler. This fault typically means that the boiler is unable to detect water flow, which can prevent it from heating water effectively.
Common Causes
- Blocked Flow Switch: Debris or limescale buildup can obstruct the flow switch, preventing it from functioning properly.
- Electrical Fault: A wiring issue or a malfunctioning component within the flow switch can lead to incorrect readings and trigger the fault code.
Can I fix it myself? (DIY)
It is advisable to call a Gas Safe Engineer to address this issue, as it involves gas and electrical components that can be dangerous if handled improperly. Attempting to fix it yourself may void warranties or lead to further complications.
Estimated Repair Cost (2026 UK Prices)
The estimated repair cost for resolving the F45 fault code is around £150 to £250. This includes the cost of a new flow switch and labour, as replacement parts for this model can be relatively expensive.