What does the Glow-worm Energy F42 fault code mean?
The F42 fault code indicates a domestic hot water (DHW) flow fault in the Glow-worm Energy boiler. This typically means that the boiler is unable to detect the required flow of water needed to heat the hot water supply.
Common Causes
- Blocked DHW Flow Sensor: A blockage in the flow sensor can prevent accurate readings, leading to the F42 fault.
- Low Water Pressure: Insufficient water pressure can disrupt the flow necessary for the boiler to operate correctly.
Can I fix it myself? (DIY)
It is advisable to call a Gas Safe Engineer for this issue, as it may involve gas or electrical components that require professional handling. Attempting to fix it yourself could pose safety risks.
Estimated Repair Cost (2026 UK Prices)
The estimated repair cost for resolving the F42 fault could be around £150 to £250, primarily depending on whether the flow sensor needs cleaning or replacement, as well as any additional labour costs involved.